The Tor Browser: dom/base/nsFocusManager.cpp@6474c204b198 (annotated)

dom/base/nsFocusManager.cpp@6474c204b198 (annotated)

dom/base/nsFocusManager.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 #include "mozilla/dom/TabParent.h"
 #include "nsFocusManager.h"
 #include "nsIInterfaceRequestorUtils.h"
 #include "nsGkAtoms.h"
 #include "nsContentUtils.h"
 #include "nsIDocument.h"
 #include "nsIDOMWindow.h"
 #include "nsPIDOMWindow.h"
 #include "nsIDOMElement.h"
 #include "nsIDOMDocument.h"
 #include "nsIDOMRange.h"
 #include "nsIHTMLDocument.h"
 #include "nsIDocShell.h"
 #include "nsIDocShellTreeOwner.h"
 #include "nsLayoutUtils.h"
 #include "nsIPresShell.h"
 #include "nsFrameTraversal.h"
 #include "nsIWebNavigation.h"
 #include "nsCaret.h"
 #include "nsIBaseWindow.h"
 #include "nsViewManager.h"
 #include "nsFrameSelection.h"
 #include "mozilla/dom/Selection.h"
 #include "nsXULPopupManager.h"
 #include "nsIScriptObjectPrincipal.h"
 #include "nsIPrincipal.h"
 #include "nsIObserverService.h"
 #include "nsIObjectFrame.h"
 #include "nsBindingManager.h"
 #include "nsStyleCoord.h"
 #include "mozilla/ContentEvents.h"
 #include "mozilla/dom/Element.h"
 #include "mozilla/EventDispatcher.h"
 #include "mozilla/EventStateManager.h"
 #include "mozilla/EventStates.h"
 #include "mozilla/IMEStateManager.h"
 #include "mozilla/LookAndFeel.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/Services.h"
 #include <algorithm>
 #ifdef MOZ_XUL
 #include "nsIDOMXULTextboxElement.h"
 #include "nsIDOMXULMenuListElement.h"
 #endif
 #ifdef ACCESSIBILITY
 #include "nsAccessibilityService.h"
 #endif
 #ifndef XP_MACOSX
 #include "nsIScriptError.h"
 #endif
 using namespace mozilla;
 using namespace mozilla::dom;
 using namespace mozilla::widget;
 #ifdef PR_LOGGING
 // Two types of focus pr logging are available:
 //   'Focus' for normal focus manager calls
 //   'FocusNavigation' for tab and document navigation
 PRLogModuleInfo* gFocusLog;
 PRLogModuleInfo* gFocusNavigationLog;
 #define LOGFOCUS(args) PR_LOG(gFocusLog, 4, args)
 #define LOGFOCUSNAVIGATION(args) PR_LOG(gFocusNavigationLog, 4, args)
 #define LOGTAG(log, format, content)                            \
   {                                                             \
     nsAutoCString tag(NS_LITERAL_CSTRING("(none)"));            \
     if (content) {                                              \
       content->Tag()->ToUTF8String(tag);                        \
     }                                                           \
     PR_LOG(log, 4, (format, tag.get()));                        \
   }
 #define LOGCONTENT(format, content) LOGTAG(gFocusLog, format, content)
 #define LOGCONTENTNAVIGATION(format, content) LOGTAG(gFocusNavigationLog, format, content)
 #else
 #define LOGFOCUS(args)
 #define LOGFOCUSNAVIGATION(args)
 #define LOGCONTENT(format, content)
 #define LOGCONTENTNAVIGATION(format, content)
 #endif
 struct nsDelayedBlurOrFocusEvent
 {
   nsDelayedBlurOrFocusEvent(uint32_t aType,
                             nsIPresShell* aPresShell,
                             nsIDocument* aDocument,
                             EventTarget* aTarget)
    : mType(aType),
      mPresShell(aPresShell),
      mDocument(aDocument),
      mTarget(aTarget) { }
   nsDelayedBlurOrFocusEvent(const nsDelayedBlurOrFocusEvent& aOther)
    : mType(aOther.mType),
      mPresShell(aOther.mPresShell),
      mDocument(aOther.mDocument),
      mTarget(aOther.mTarget) { }
   uint32_t mType;
   nsCOMPtr<nsIPresShell> mPresShell;
   nsCOMPtr<nsIDocument> mDocument;
   nsCOMPtr<EventTarget> mTarget;
 };
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsFocusManager)
   NS_INTERFACE_MAP_ENTRY(nsIFocusManager)
   NS_INTERFACE_MAP_ENTRY(nsIObserver)
   NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
   NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIFocusManager)
 NS_INTERFACE_MAP_END
 NS_IMPL_CYCLE_COLLECTING_ADDREF(nsFocusManager)
 NS_IMPL_CYCLE_COLLECTING_RELEASE(nsFocusManager)
 NS_IMPL_CYCLE_COLLECTION(nsFocusManager,
                          mActiveWindow,
                          mFocusedWindow,
                          mFocusedContent,
                          mFirstBlurEvent,
                          mFirstFocusEvent,
                          mWindowBeingLowered)
 nsFocusManager* nsFocusManager::sInstance = nullptr;
 bool nsFocusManager::sMouseFocusesFormControl = false;
 bool nsFocusManager::sTestMode = false;
 static const char* kObservedPrefs[] = {
   "accessibility.browsewithcaret",
   "accessibility.tabfocus_applies_to_xul",
   "accessibility.mouse_focuses_formcontrol",
   "focusmanager.testmode",
   nullptr
 };
 nsFocusManager::nsFocusManager()
 { }
 nsFocusManager::~nsFocusManager()
 {
   Preferences::RemoveObservers(this, kObservedPrefs);
   nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
   if (obs) {
     obs->RemoveObserver(this, "xpcom-shutdown");
   }
 }
 // static
 nsresult
 nsFocusManager::Init()
 {
   nsFocusManager* fm = new nsFocusManager();
   NS_ENSURE_TRUE(fm, NS_ERROR_OUT_OF_MEMORY);
   NS_ADDREF(fm);
   sInstance = fm;
 #ifdef PR_LOGGING
   gFocusLog = PR_NewLogModule("Focus");
   gFocusNavigationLog = PR_NewLogModule("FocusNavigation");
 #endif
   nsIContent::sTabFocusModelAppliesToXUL =
     Preferences::GetBool("accessibility.tabfocus_applies_to_xul",
                          nsIContent::sTabFocusModelAppliesToXUL);
   sMouseFocusesFormControl =
     Preferences::GetBool("accessibility.mouse_focuses_formcontrol", false);
   sTestMode = Preferences::GetBool("focusmanager.testmode", false);
   Preferences::AddWeakObservers(fm, kObservedPrefs);
   nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
   if (obs) {
     obs->AddObserver(fm, "xpcom-shutdown", true);
   }
   return NS_OK;
 }
 // static
 void
 nsFocusManager::Shutdown()
 {
   NS_IF_RELEASE(sInstance);
 }
 NS_IMETHODIMP
 nsFocusManager::Observe(nsISupports *aSubject,
                         const char *aTopic,
                         const char16_t *aData)
 {
   if (!nsCRT::strcmp(aTopic, NS_PREFBRANCH_PREFCHANGE_TOPIC_ID)) {
     nsDependentString data(aData);
     if (data.EqualsLiteral("accessibility.browsewithcaret")) {
       UpdateCaretForCaretBrowsingMode();
     }
     else if (data.EqualsLiteral("accessibility.tabfocus_applies_to_xul")) {
       nsIContent::sTabFocusModelAppliesToXUL =
         Preferences::GetBool("accessibility.tabfocus_applies_to_xul",
                              nsIContent::sTabFocusModelAppliesToXUL);
     }
     else if (data.EqualsLiteral("accessibility.mouse_focuses_formcontrol")) {
       sMouseFocusesFormControl =
         Preferences::GetBool("accessibility.mouse_focuses_formcontrol",
                              false);
     }
     else if (data.EqualsLiteral("focusmanager.testmode")) {
       sTestMode = Preferences::GetBool("focusmanager.testmode", false);
     }
   } else if (!nsCRT::strcmp(aTopic, "xpcom-shutdown")) {
     mActiveWindow = nullptr;
     mFocusedWindow = nullptr;
     mFocusedContent = nullptr;
     mFirstBlurEvent = nullptr;
     mFirstFocusEvent = nullptr;
     mWindowBeingLowered = nullptr;
     mDelayedBlurFocusEvents.Clear();
     mMouseDownEventHandlingDocument = nullptr;
   }
   return NS_OK;
 }
 // given a frame content node, retrieve the nsIDOMWindow displayed in it
 static nsPIDOMWindow*
 GetContentWindow(nsIContent* aContent)
 {
   nsIDocument* doc = aContent->GetCurrentDoc();
   if (doc) {
     nsIDocument* subdoc = doc->GetSubDocumentFor(aContent);
     if (subdoc)
       return subdoc->GetWindow();
   }
   return nullptr;
 }
 // get the current window for the given content node
 static nsPIDOMWindow*
 GetCurrentWindow(nsIContent* aContent)
 {
   nsIDocument *doc = aContent->GetCurrentDoc();
   return doc ? doc->GetWindow() : nullptr;
 }
 // static
 nsIContent*
 nsFocusManager::GetFocusedDescendant(nsPIDOMWindow* aWindow, bool aDeep,
                                      nsPIDOMWindow** aFocusedWindow)
 {
   NS_ENSURE_TRUE(aWindow, nullptr);
   *aFocusedWindow = nullptr;
   nsIContent* currentContent = nullptr;
   nsPIDOMWindow* window = aWindow->GetOuterWindow();
   while (window) {
     *aFocusedWindow = window;
     currentContent = window->GetFocusedNode();
     if (!currentContent || !aDeep)
       break;
     window = GetContentWindow(currentContent);
   }
   NS_IF_ADDREF(*aFocusedWindow);
   return currentContent;
 }
 // static
 nsIContent*
 nsFocusManager::GetRedirectedFocus(nsIContent* aContent)
 {
 #ifdef MOZ_XUL
   if (aContent->IsXUL()) {
     nsCOMPtr<nsIDOMNode> inputField;
     nsCOMPtr<nsIDOMXULTextBoxElement> textbox = do_QueryInterface(aContent);
     if (textbox) {
       textbox->GetInputField(getter_AddRefs(inputField));
     }
     else {
       nsCOMPtr<nsIDOMXULMenuListElement> menulist = do_QueryInterface(aContent);
       if (menulist) {
         menulist->GetInputField(getter_AddRefs(inputField));
       }
       else if (aContent->Tag() == nsGkAtoms::scale) {
         nsCOMPtr<nsIDocument> doc = aContent->GetCurrentDoc();
         if (!doc)
           return nullptr;
         nsINodeList* children = doc->BindingManager()->GetAnonymousNodesFor(aContent);
         if (children) {
           nsIContent* child = children->Item(0);
           if (child && child->Tag() == nsGkAtoms::slider)
             return child;
         }
       }
     }
     if (inputField) {
       nsCOMPtr<nsIContent> retval = do_QueryInterface(inputField);
       return retval;
     }
   }
 #endif
   return nullptr;
 }
 // static
 InputContextAction::Cause
 nsFocusManager::GetFocusMoveActionCause(uint32_t aFlags)
 {
   if (aFlags & nsIFocusManager::FLAG_BYMOUSE) {
     return InputContextAction::CAUSE_MOUSE;
   } else if (aFlags & nsIFocusManager::FLAG_BYKEY) {
     return InputContextAction::CAUSE_KEY;
   }
   return InputContextAction::CAUSE_UNKNOWN;
 }
 NS_IMETHODIMP
 nsFocusManager::GetActiveWindow(nsIDOMWindow** aWindow)
 {
   NS_IF_ADDREF(*aWindow = mActiveWindow);
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::SetActiveWindow(nsIDOMWindow* aWindow)
 {
   // only top-level windows can be made active
   nsCOMPtr<nsPIDOMWindow> piWindow = do_QueryInterface(aWindow);
   if (piWindow)
       piWindow = piWindow->GetOuterWindow();
   NS_ENSURE_TRUE(piWindow && (piWindow == piWindow->GetPrivateRoot()),
                  NS_ERROR_INVALID_ARG);
   RaiseWindow(piWindow);
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::GetFocusedWindow(nsIDOMWindow** aFocusedWindow)
 {
   NS_IF_ADDREF(*aFocusedWindow = mFocusedWindow);
   return NS_OK;
 }
 NS_IMETHODIMP nsFocusManager::SetFocusedWindow(nsIDOMWindow* aWindowToFocus)
 {
   LOGFOCUS(("<<SetFocusedWindow begin>>"));
   nsCOMPtr<nsPIDOMWindow> windowToFocus(do_QueryInterface(aWindowToFocus));
   NS_ENSURE_TRUE(windowToFocus, NS_ERROR_FAILURE);
   windowToFocus = windowToFocus->GetOuterWindow();
   nsCOMPtr<nsIContent> frameContent =
     do_QueryInterface(windowToFocus->GetFrameElementInternal());
   if (frameContent) {
     // pass false for aFocusChanged so that the caret does not get updated
     // and scrolling does not occur.
     SetFocusInner(frameContent, 0, false, true);
   }
   else {
     // this is a top-level window. If the window has a child frame focused,
     // clear the focus. Otherwise, focus should already be in this frame, or
     // already cleared. This ensures that focus will be in this frame and not
     // in a child.
     nsIContent* content = windowToFocus->GetFocusedNode();
     if (content) {
       nsCOMPtr<nsIDOMWindow> childWindow = GetContentWindow(content);
       if (childWindow)
         ClearFocus(windowToFocus);
     }
   }
   nsCOMPtr<nsPIDOMWindow> rootWindow = windowToFocus->GetPrivateRoot();
   if (rootWindow)
     RaiseWindow(rootWindow);
   LOGFOCUS(("<<SetFocusedWindow end>>"));
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::GetFocusedElement(nsIDOMElement** aFocusedElement)
 {
   if (mFocusedContent)
     CallQueryInterface(mFocusedContent, aFocusedElement);
   else
     *aFocusedElement = nullptr;
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::GetLastFocusMethod(nsIDOMWindow* aWindow, uint32_t* aLastFocusMethod)
 {
   // the focus method is stored on the inner window
   nsCOMPtr<nsPIDOMWindow> window(do_QueryInterface(aWindow));
   if (window)
     window = window->GetCurrentInnerWindow();
   if (!window)
     window = mFocusedWindow;
   *aLastFocusMethod = window ? window->GetFocusMethod() : 0;
   NS_ASSERTION((*aLastFocusMethod & FOCUSMETHOD_MASK) == *aLastFocusMethod,
                "invalid focus method");
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::SetFocus(nsIDOMElement* aElement, uint32_t aFlags)
 {
   LOGFOCUS(("<<SetFocus begin>>"));
   nsCOMPtr<nsIContent> newFocus = do_QueryInterface(aElement);
   NS_ENSURE_ARG(newFocus);
   SetFocusInner(newFocus, aFlags, true, true);
   LOGFOCUS(("<<SetFocus end>>"));
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::ElementIsFocusable(nsIDOMElement* aElement, uint32_t aFlags,
                                    bool* aIsFocusable)
 {
   NS_ENSURE_TRUE(aElement, NS_ERROR_INVALID_ARG);
   nsCOMPtr<nsIContent> aContent = do_QueryInterface(aElement);
   *aIsFocusable = CheckIfFocusable(aContent, aFlags) != nullptr;
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::MoveFocus(nsIDOMWindow* aWindow, nsIDOMElement* aStartElement,
                           uint32_t aType, uint32_t aFlags, nsIDOMElement** aElement)
 {
   *aElement = nullptr;
 #ifdef PR_LOGGING
   LOGFOCUS(("<<MoveFocus begin Type: %d Flags: %x>>", aType, aFlags));
   if (PR_LOG_TEST(gFocusLog, PR_LOG_DEBUG) && mFocusedWindow) {
     nsIDocument* doc = mFocusedWindow->GetExtantDoc();
     if (doc && doc->GetDocumentURI()) {
       nsAutoCString spec;
       doc->GetDocumentURI()->GetSpec(spec);
       LOGFOCUS((" Focused Window: %p %s", mFocusedWindow.get(), spec.get()));
     }
   }
   LOGCONTENT("  Current Focus: %s", mFocusedContent.get());
 #endif
   // use FLAG_BYMOVEFOCUS when switching focus with MoveFocus unless one of
   // the other focus methods is already set, or we're just moving to the root
   // or caret position.
   if (aType != MOVEFOCUS_ROOT && aType != MOVEFOCUS_CARET &&
       (aFlags & FOCUSMETHOD_MASK) == 0) {
     aFlags |= FLAG_BYMOVEFOCUS;
   }
   nsCOMPtr<nsPIDOMWindow> window;
   nsCOMPtr<nsIContent> startContent;
   if (aStartElement) {
     startContent = do_QueryInterface(aStartElement);
     NS_ENSURE_TRUE(startContent, NS_ERROR_INVALID_ARG);
     window = GetCurrentWindow(startContent);
   }
   else {
     window = aWindow ? do_QueryInterface(aWindow) : mFocusedWindow;
     NS_ENSURE_TRUE(window, NS_ERROR_FAILURE);
     window = window->GetOuterWindow();
   }
   NS_ENSURE_TRUE(window, NS_ERROR_FAILURE);
   bool noParentTraversal = aFlags & FLAG_NOPARENTFRAME;
   nsCOMPtr<nsIContent> newFocus;
   nsresult rv = DetermineElementToMoveFocus(window, startContent, aType, noParentTraversal,
                                             getter_AddRefs(newFocus));
   NS_ENSURE_SUCCESS(rv, rv);
   LOGCONTENTNAVIGATION("Element to be focused: %s", newFocus.get());
   if (newFocus) {
     // for caret movement, pass false for the aFocusChanged argument,
     // otherwise the caret will end up moving to the focus position. This
     // would be a problem because the caret would move to the beginning of the
     // focused link making it impossible to navigate the caret over a link.
     SetFocusInner(newFocus, aFlags, aType != MOVEFOCUS_CARET, true);
     CallQueryInterface(newFocus, aElement);
   }
   else if (aType == MOVEFOCUS_ROOT || aType == MOVEFOCUS_CARET) {
     // no content was found, so clear the focus for these two types.
     ClearFocus(window);
   }
   LOGFOCUS(("<<MoveFocus end>>"));
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::ClearFocus(nsIDOMWindow* aWindow)
 {
   LOGFOCUS(("<<ClearFocus begin>>"));
   // if the window to clear is the focused window or an ancestor of the
   // focused window, then blur the existing focused content. Otherwise, the
   // focus is somewhere else so just update the current node.
   nsCOMPtr<nsPIDOMWindow> window(do_QueryInterface(aWindow));
   NS_ENSURE_TRUE(window, NS_ERROR_INVALID_ARG);
   window = window->GetOuterWindow();
   NS_ENSURE_TRUE(window, NS_ERROR_INVALID_ARG);
   if (IsSameOrAncestor(window, mFocusedWindow)) {
     bool isAncestor = (window != mFocusedWindow);
     if (Blur(window, nullptr, isAncestor, true)) {
       // if we are clearing the focus on an ancestor of the focused window,
       // the ancestor will become the new focused window, so focus it
       if (isAncestor)
         Focus(window, nullptr, 0, true, false, false, true);
     }
   }
   else {
     window->SetFocusedNode(nullptr);
   }
   LOGFOCUS(("<<ClearFocus end>>"));
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::GetFocusedElementForWindow(nsIDOMWindow* aWindow,
                                            bool aDeep,
                                            nsIDOMWindow** aFocusedWindow,
                                            nsIDOMElement** aElement)
 {
   *aElement = nullptr;
   if (aFocusedWindow)
     *aFocusedWindow = nullptr;
   nsCOMPtr<nsPIDOMWindow> window(do_QueryInterface(aWindow));
   NS_ENSURE_TRUE(window, NS_ERROR_INVALID_ARG);
   window = window->GetOuterWindow();
   NS_ENSURE_TRUE(window, NS_ERROR_INVALID_ARG);
   nsCOMPtr<nsPIDOMWindow> focusedWindow;
   nsCOMPtr<nsIContent> focusedContent =
     GetFocusedDescendant(window, aDeep, getter_AddRefs(focusedWindow));
   if (focusedContent)
     CallQueryInterface(focusedContent, aElement);
   if (aFocusedWindow)
     NS_IF_ADDREF(*aFocusedWindow = focusedWindow);
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::MoveCaretToFocus(nsIDOMWindow* aWindow)
 {
   nsCOMPtr<nsIWebNavigation> webnav = do_GetInterface(aWindow);
   nsCOMPtr<nsIDocShellTreeItem> dsti = do_QueryInterface(webnav);
   if (dsti) {
     if (dsti->ItemType() != nsIDocShellTreeItem::typeChrome) {
       nsCOMPtr<nsIDocShell> docShell = do_QueryInterface(dsti);
       NS_ENSURE_TRUE(docShell, NS_ERROR_FAILURE);
       // don't move the caret for editable documents
       bool isEditable;
       docShell->GetEditable(&isEditable);
       if (isEditable)
         return NS_OK;
       nsCOMPtr<nsIPresShell> presShell = docShell->GetPresShell();
       NS_ENSURE_TRUE(presShell, NS_ERROR_FAILURE);
       nsCOMPtr<nsPIDOMWindow> window(do_QueryInterface(aWindow));
       nsCOMPtr<nsIContent> content = window->GetFocusedNode();
       if (content)
         MoveCaretToFocus(presShell, content);
     }
   }
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::WindowRaised(nsIDOMWindow* aWindow)
 {
   nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(aWindow);
   NS_ENSURE_TRUE(window && window->IsOuterWindow(), NS_ERROR_INVALID_ARG);
 #ifdef PR_LOGGING
   if (PR_LOG_TEST(gFocusLog, PR_LOG_DEBUG)) {
     LOGFOCUS(("Window %p Raised [Currently: %p %p]", aWindow, mActiveWindow.get(), mFocusedWindow.get()));
     nsAutoCString spec;
     nsIDocument* doc = window->GetExtantDoc();
     if (doc && doc->GetDocumentURI()) {
       doc->GetDocumentURI()->GetSpec(spec);
       LOGFOCUS(("  Raised Window: %p %s", aWindow, spec.get()));
     }
     if (mActiveWindow) {
       doc = mActiveWindow->GetExtantDoc();
       if (doc && doc->GetDocumentURI()) {
         doc->GetDocumentURI()->GetSpec(spec);
         LOGFOCUS(("  Active Window: %p %s", mActiveWindow.get(), spec.get()));
       }
     }
   }
 #endif
   if (mActiveWindow == window) {
     // The window is already active, so there is no need to focus anything,
     // but make sure that the right widget is focused. This is a special case
     // for Windows because when restoring a minimized window, a second
     // activation will occur and the top-level widget could be focused instead
     // of the child we want. We solve this by calling SetFocus to ensure that
     // what the focus manager thinks should be the current widget is actually
     // focused.
     EnsureCurrentWidgetFocused();
     return NS_OK;
   }
   // lower the existing window, if any. This shouldn't happen usually.
   if (mActiveWindow)
     WindowLowered(mActiveWindow);
   nsCOMPtr<nsIWebNavigation> webnav(do_GetInterface(aWindow));
   nsCOMPtr<nsIDocShellTreeItem> docShellAsItem(do_QueryInterface(webnav));
   // If there's no docShellAsItem, this window must have been closed,
   // in that case there is no tree owner.
   NS_ENSURE_TRUE(docShellAsItem, NS_OK);
   // set this as the active window
   mActiveWindow = window;
   // ensure that the window is enabled and visible
   nsCOMPtr<nsIDocShellTreeOwner> treeOwner;
   docShellAsItem->GetTreeOwner(getter_AddRefs(treeOwner));
   nsCOMPtr<nsIBaseWindow> baseWindow = do_QueryInterface(treeOwner);
   if (baseWindow) {
     bool isEnabled = true;
     if (NS_SUCCEEDED(baseWindow->GetEnabled(&isEnabled)) && !isEnabled) {
       return NS_ERROR_FAILURE;
     }
     if (!sTestMode) {
       baseWindow->SetVisibility(true);
     }
   }
   // inform the DOM window that it has activated, so that the active attribute
   // is updated on the window
   window->ActivateOrDeactivate(true);
   // send activate event
   nsContentUtils::DispatchTrustedEvent(window->GetExtantDoc(),
                                        window,
                                        NS_LITERAL_STRING("activate"),
                                        true, true, nullptr);
   // retrieve the last focused element within the window that was raised
   nsCOMPtr<nsPIDOMWindow> currentWindow;
   nsCOMPtr<nsIContent> currentFocus =
     GetFocusedDescendant(window, true, getter_AddRefs(currentWindow));
   NS_ASSERTION(currentWindow, "window raised with no window current");
   if (!currentWindow)
     return NS_OK;
   nsCOMPtr<nsIDocShell> currentDocShell = currentWindow->GetDocShell();
   nsCOMPtr<nsIPresShell> presShell = currentDocShell->GetPresShell();
   if (presShell) {
     // disable selection mousedown state on activation
     // XXXndeakin P3 not sure if this is necessary, but it doesn't hurt
     nsRefPtr<nsFrameSelection> frameSelection = presShell->FrameSelection();
     frameSelection->SetMouseDownState(false);
   }
   Focus(currentWindow, currentFocus, 0, true, false, true, true);
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::WindowLowered(nsIDOMWindow* aWindow)
 {
   nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(aWindow);
   NS_ENSURE_TRUE(window && window->IsOuterWindow(), NS_ERROR_INVALID_ARG);
 #ifdef PR_LOGGING
   if (PR_LOG_TEST(gFocusLog, PR_LOG_DEBUG)) {
     LOGFOCUS(("Window %p Lowered [Currently: %p %p]", aWindow, mActiveWindow.get(), mFocusedWindow.get()));
     nsAutoCString spec;
     nsIDocument* doc = window->GetExtantDoc();
     if (doc && doc->GetDocumentURI()) {
       doc->GetDocumentURI()->GetSpec(spec);
       LOGFOCUS(("  Lowered Window: %s", spec.get()));
     }
     if (mActiveWindow) {
       doc = mActiveWindow->GetExtantDoc();
       if (doc && doc->GetDocumentURI()) {
         doc->GetDocumentURI()->GetSpec(spec);
         LOGFOCUS(("  Active Window: %s", spec.get()));
       }
     }
   }
 #endif
   if (mActiveWindow != window)
     return NS_OK;
   // clear the mouse capture as the active window has changed
   nsIPresShell::SetCapturingContent(nullptr, 0);
   // inform the DOM window that it has deactivated, so that the active
   // attribute is updated on the window
   window->ActivateOrDeactivate(false);
   // send deactivate event
   nsContentUtils::DispatchTrustedEvent(window->GetExtantDoc(),
                                        window,
                                        NS_LITERAL_STRING("deactivate"),
                                        true, true, nullptr);
   // keep track of the window being lowered, so that attempts to raise the
   // window can be prevented until we return. Otherwise, focus can get into
   // an unusual state.
   mWindowBeingLowered = mActiveWindow;
   mActiveWindow = nullptr;
   if (mFocusedWindow)
     Blur(nullptr, nullptr, true, true);
   mWindowBeingLowered = nullptr;
   return NS_OK;
 }
 nsresult
 nsFocusManager::ContentRemoved(nsIDocument* aDocument, nsIContent* aContent)
 {
   NS_ENSURE_ARG(aDocument);
   NS_ENSURE_ARG(aContent);
   nsPIDOMWindow *window = aDocument->GetWindow();
   if (!window)
     return NS_OK;
   // if the content is currently focused in the window, or is an ancestor
   // of the currently focused element, reset the focus within that window.
   nsIContent* content = window->GetFocusedNode();
   if (content && nsContentUtils::ContentIsDescendantOf(content, aContent)) {
     bool shouldShowFocusRing = window->ShouldShowFocusRing();
     window->SetFocusedNode(nullptr);
     // if this window is currently focused, clear the global focused
     // element as well, but don't fire any events.
     if (window == mFocusedWindow) {
       mFocusedContent = nullptr;
     }
     else {
       // Check if the node that was focused is an iframe or similar by looking
       // if it has a subdocument. This would indicate that this focused iframe
       // and its descendants will be going away. We will need to move the
       // focus somewhere else, so just clear the focus in the toplevel window
       // so that no element is focused.
       nsIDocument* subdoc = aDocument->GetSubDocumentFor(content);
       if (subdoc) {
         nsCOMPtr<nsISupports> container = subdoc->GetContainer();
         nsCOMPtr<nsPIDOMWindow> childWindow = do_GetInterface(container);
         if (childWindow && IsSameOrAncestor(childWindow, mFocusedWindow)) {
           ClearFocus(mActiveWindow);
         }
       }
     }
     NotifyFocusStateChange(content, shouldShowFocusRing, false);
   }
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::WindowShown(nsIDOMWindow* aWindow, bool aNeedsFocus)
 {
   nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(aWindow);
   NS_ENSURE_TRUE(window, NS_ERROR_INVALID_ARG);
   window = window->GetOuterWindow();
 #ifdef PR_LOGGING
   if (PR_LOG_TEST(gFocusLog, PR_LOG_DEBUG)) {
     LOGFOCUS(("Window %p Shown [Currently: %p %p]", window.get(), mActiveWindow.get(), mFocusedWindow.get()));
     nsAutoCString spec;
     nsIDocument* doc = window->GetExtantDoc();
     if (doc && doc->GetDocumentURI()) {
       doc->GetDocumentURI()->GetSpec(spec);
       LOGFOCUS(("Shown Window: %s", spec.get()));
     }
     if (mFocusedWindow) {
       doc = mFocusedWindow->GetExtantDoc();
       if (doc && doc->GetDocumentURI()) {
         doc->GetDocumentURI()->GetSpec(spec);
         LOGFOCUS((" Focused Window: %s", spec.get()));
       }
     }
   }
 #endif
   if (mFocusedWindow != window)
     return NS_OK;
   if (aNeedsFocus) {
     nsCOMPtr<nsPIDOMWindow> currentWindow;
     nsCOMPtr<nsIContent> currentFocus =
       GetFocusedDescendant(window, true, getter_AddRefs(currentWindow));
     if (currentWindow)
       Focus(currentWindow, currentFocus, 0, true, false, false, true);
   }
   else {
     // Sometimes, an element in a window can be focused before the window is
     // visible, which would mean that the widget may not be properly focused.
     // When the window becomes visible, make sure the right widget is focused.
     EnsureCurrentWidgetFocused();
   }
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::WindowHidden(nsIDOMWindow* aWindow)
 {
   // if there is no window or it is not the same or an ancestor of the
   // currently focused window, just return, as the current focus will not
   // be affected.
   nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(aWindow);
   NS_ENSURE_TRUE(window, NS_ERROR_INVALID_ARG);
   window = window->GetOuterWindow();
 #ifdef PR_LOGGING
   if (PR_LOG_TEST(gFocusLog, PR_LOG_DEBUG)) {
     LOGFOCUS(("Window %p Hidden [Currently: %p %p]", window.get(), mActiveWindow.get(), mFocusedWindow.get()));
     nsAutoCString spec;
     nsIDocument* doc = window->GetExtantDoc();
     if (doc && doc->GetDocumentURI()) {
       doc->GetDocumentURI()->GetSpec(spec);
       LOGFOCUS(("  Hide Window: %s", spec.get()));
     }
     if (mFocusedWindow) {
       doc = mFocusedWindow->GetExtantDoc();
       if (doc && doc->GetDocumentURI()) {
         doc->GetDocumentURI()->GetSpec(spec);
         LOGFOCUS(("  Focused Window: %s", spec.get()));
       }
     }
     if (mActiveWindow) {
       doc = mActiveWindow->GetExtantDoc();
       if (doc && doc->GetDocumentURI()) {
         doc->GetDocumentURI()->GetSpec(spec);
         LOGFOCUS(("  Active Window: %s", spec.get()));
       }
     }
   }
 #endif
   if (!IsSameOrAncestor(window, mFocusedWindow))
     return NS_OK;
   // at this point, we know that the window being hidden is either the focused
   // window, or an ancestor of the focused window. Either way, the focus is no
   // longer valid, so it needs to be updated.
   nsCOMPtr<nsIContent> oldFocusedContent = mFocusedContent.forget();
   nsCOMPtr<nsIDocShell> focusedDocShell = mFocusedWindow->GetDocShell();
   nsCOMPtr<nsIPresShell> presShell = focusedDocShell->GetPresShell();
   if (oldFocusedContent && oldFocusedContent->IsInDoc()) {
     NotifyFocusStateChange(oldFocusedContent,
                            mFocusedWindow->ShouldShowFocusRing(),
                            false);
     window->UpdateCommands(NS_LITERAL_STRING("focus"));
     if (presShell) {
       SendFocusOrBlurEvent(NS_BLUR_CONTENT, presShell,
                            oldFocusedContent->GetCurrentDoc(),
                            oldFocusedContent, 1, false);
     }
   }
   nsPresContext* focusedPresContext =
     presShell ? presShell->GetPresContext() : nullptr;
   IMEStateManager::OnChangeFocus(focusedPresContext, nullptr,
                                  GetFocusMoveActionCause(0));
   if (presShell) {
     SetCaretVisible(presShell, false, nullptr);
   }
   // if the docshell being hidden is being destroyed, then we want to move
   // focus somewhere else. Call ClearFocus on the toplevel window, which
   // will have the effect of clearing the focus and moving the focused window
   // to the toplevel window. But if the window isn't being destroyed, we are
   // likely just loading a new document in it, so we want to maintain the
   // focused window so that the new document gets properly focused.
   bool beingDestroyed;
   nsCOMPtr<nsIDocShell> docShellBeingHidden = window->GetDocShell();
   docShellBeingHidden->IsBeingDestroyed(&beingDestroyed);
   if (beingDestroyed) {
     // There is usually no need to do anything if a toplevel window is going
     // away, as we assume that WindowLowered will be called. However, this may
     // not happen if nsIAppStartup::eForceQuit is used to quit, and can cause
     // a leak. So if the active window is being destroyed, call WindowLowered
     // directly.
     NS_ASSERTION(mFocusedWindow->IsOuterWindow(), "outer window expected");
     if (mActiveWindow == mFocusedWindow || mActiveWindow == window)
       WindowLowered(mActiveWindow);
     else
       ClearFocus(mActiveWindow);
     return NS_OK;
   }
   // if the window being hidden is an ancestor of the focused window, adjust
   // the focused window so that it points to the one being hidden. This
   // ensures that the focused window isn't in a chain of frames that doesn't
   // exist any more.
   if (window != mFocusedWindow) {
     nsCOMPtr<nsIWebNavigation> webnav(do_GetInterface(mFocusedWindow));
     nsCOMPtr<nsIDocShellTreeItem> dsti = do_QueryInterface(webnav);
     if (dsti) {
       nsCOMPtr<nsIDocShellTreeItem> parentDsti;
       dsti->GetParent(getter_AddRefs(parentDsti));
       nsCOMPtr<nsPIDOMWindow> parentWindow = do_GetInterface(parentDsti);
       if (parentWindow)
         parentWindow->SetFocusedNode(nullptr);
     }
     SetFocusedWindowInternal(window);
   }
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::FireDelayedEvents(nsIDocument* aDocument)
 {
   NS_ENSURE_ARG(aDocument);
   // fire any delayed focus and blur events in the same order that they were added
   for (uint32_t i = 0; i < mDelayedBlurFocusEvents.Length(); i++) {
     if (mDelayedBlurFocusEvents[i].mDocument == aDocument) {
       if (!aDocument->GetInnerWindow() ||
           !aDocument->GetInnerWindow()->IsCurrentInnerWindow()) {
         // If the document was navigated away from or is defunct, don't bother
         // firing events on it. Note the symmetry between this condition and
         // the similar one in nsDocument.cpp:FireOrClearDelayedEvents.
         mDelayedBlurFocusEvents.RemoveElementAt(i);
         --i;
       } else if (!aDocument->EventHandlingSuppressed()) {
         uint32_t type = mDelayedBlurFocusEvents[i].mType;
         nsCOMPtr<EventTarget> target = mDelayedBlurFocusEvents[i].mTarget;
         nsCOMPtr<nsIPresShell> presShell = mDelayedBlurFocusEvents[i].mPresShell;
         mDelayedBlurFocusEvents.RemoveElementAt(i);
         SendFocusOrBlurEvent(type, presShell, aDocument, target, 0, false);
         --i;
       }
     }
   }
   return NS_OK;
 }
 NS_IMETHODIMP
 nsFocusManager::FocusPlugin(nsIContent* aContent)
 {
   NS_ENSURE_ARG(aContent);
   SetFocusInner(aContent, 0, true, false);
   return NS_OK;
 }
 /* static */
 void
 nsFocusManager::NotifyFocusStateChange(nsIContent* aContent,
                                        bool aWindowShouldShowFocusRing,
                                        bool aGettingFocus)
 {
   if (!aContent->IsElement()) {
     return;
   }
   EventStates eventState = NS_EVENT_STATE_FOCUS;
   if (aWindowShouldShowFocusRing) {
     eventState |= NS_EVENT_STATE_FOCUSRING;
   }
   if (aGettingFocus) {
     aContent->AsElement()->AddStates(eventState);
   } else {
     aContent->AsElement()->RemoveStates(eventState);
   }
 }
 // static
 void
 nsFocusManager::EnsureCurrentWidgetFocused()
 {
   if (!mFocusedWindow || sTestMode)
     return;
   // get the main child widget for the focused window and ensure that the
   // platform knows that this widget is focused.
   nsCOMPtr<nsIDocShell> docShell = mFocusedWindow->GetDocShell();
   if (docShell) {
     nsCOMPtr<nsIPresShell> presShell = docShell->GetPresShell();
     if (presShell) {
       nsViewManager* vm = presShell->GetViewManager();
       if (vm) {
         nsCOMPtr<nsIWidget> widget;
         vm->GetRootWidget(getter_AddRefs(widget));
         if (widget)
           widget->SetFocus(false);
       }
     }
   }
 }
 void
 nsFocusManager::SetFocusInner(nsIContent* aNewContent, int32_t aFlags,
                               bool aFocusChanged, bool aAdjustWidget)
 {
   // if the element is not focusable, just return and leave the focus as is
   nsCOMPtr<nsIContent> contentToFocus = CheckIfFocusable(aNewContent, aFlags);
   if (!contentToFocus)
     return;
   // check if the element to focus is a frame (iframe) containing a child
   // document. Frames are never directly focused; instead focusing a frame
   // means focus what is inside the frame. To do this, the descendant content
   // within the frame is retrieved and that will be focused instead.
   nsCOMPtr<nsPIDOMWindow> newWindow;
   nsCOMPtr<nsPIDOMWindow> subWindow = GetContentWindow(contentToFocus);
   if (subWindow) {
     contentToFocus = GetFocusedDescendant(subWindow, true, getter_AddRefs(newWindow));
     // since a window is being refocused, clear aFocusChanged so that the
     // caret position isn't updated.
     aFocusChanged = false;
   }
   // unless it was set above, retrieve the window for the element to focus
   if (!newWindow)
     newWindow = GetCurrentWindow(contentToFocus);
   // if the element is already focused, just return. Note that this happens
   // after the frame check above so that we compare the element that will be
   // focused rather than the frame it is in.
   if (!newWindow || (newWindow == mFocusedWindow && contentToFocus == mFocusedContent))
     return;
   // don't allow focus to be placed in docshells or descendants of docshells
   // that are being destroyed. Also, ensure that the page hasn't been
   // unloaded. The prevents content from being refocused during an unload event.
   nsCOMPtr<nsIDocShell> newDocShell = newWindow->GetDocShell();
   nsCOMPtr<nsIDocShell> docShell = newDocShell;
   while (docShell) {
     bool inUnload;
     docShell->GetIsInUnload(&inUnload);
     if (inUnload)
       return;
     bool beingDestroyed;
     docShell->IsBeingDestroyed(&beingDestroyed);
     if (beingDestroyed)
       return;
     nsCOMPtr<nsIDocShellTreeItem> parentDsti;
     docShell->GetParent(getter_AddRefs(parentDsti));
     docShell = do_QueryInterface(parentDsti);
   }
   // if the new element is in the same window as the currently focused element
   bool isElementInFocusedWindow = (mFocusedWindow == newWindow);
   if (!isElementInFocusedWindow && mFocusedWindow && newWindow &&
       nsContentUtils::IsHandlingKeyBoardEvent()) {
     nsCOMPtr<nsIScriptObjectPrincipal> focused =
       do_QueryInterface(mFocusedWindow);
     nsCOMPtr<nsIScriptObjectPrincipal> newFocus =
       do_QueryInterface(newWindow);
     nsIPrincipal* focusedPrincipal = focused->GetPrincipal();
     nsIPrincipal* newPrincipal = newFocus->GetPrincipal();
     if (!focusedPrincipal || !newPrincipal) {
       return;
     }
     bool subsumes = false;
     focusedPrincipal->Subsumes(newPrincipal, &subsumes);
     if (!subsumes && !nsContentUtils::IsCallerChrome()) {
       NS_WARNING("Not allowed to focus the new window!");
       return;
     }
   }
   // to check if the new element is in the active window, compare the
   // new root docshell for the new element with the active window's docshell.
   bool isElementInActiveWindow = false;
   nsCOMPtr<nsIWebNavigation> webnav = do_GetInterface(newWindow);
   nsCOMPtr<nsIDocShellTreeItem> dsti = do_QueryInterface(webnav);
   nsCOMPtr<nsPIDOMWindow> newRootWindow;
   if (dsti) {
     nsCOMPtr<nsIDocShellTreeItem> root;
     dsti->GetRootTreeItem(getter_AddRefs(root));
     newRootWindow = do_GetInterface(root);
     isElementInActiveWindow = (mActiveWindow && newRootWindow == mActiveWindow);
   }
   // Exit fullscreen if we're focusing a windowed plugin on a non-MacOSX
   // system. We don't control event dispatch to windowed plugins on non-MacOSX,
   // so we can't display the "Press ESC to leave fullscreen mode" warning on
   // key input if a windowed plugin is focused, so just exit fullscreen
   // to guard against phishing.
 #ifndef XP_MACOSX
   nsIDocument* fullscreenAncestor;
   if (contentToFocus &&
       (fullscreenAncestor = nsContentUtils::GetFullscreenAncestor(contentToFocus->OwnerDoc())) &&
       nsContentUtils::HasPluginWithUncontrolledEventDispatch(contentToFocus)) {
     nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,
                                     NS_LITERAL_CSTRING("DOM"),
                                     contentToFocus->OwnerDoc(),
                                     nsContentUtils::eDOM_PROPERTIES,
                                     "FocusedWindowedPluginWhileFullScreen");
     nsIDocument::ExitFullscreen(fullscreenAncestor, /* async */ true);
   }
 #endif
   // if the FLAG_NOSWITCHFRAME flag is used, only allow the focus to be
   // shifted away from the current element if the new shell to focus is
   // the same or an ancestor shell of the currently focused shell.
   bool allowFrameSwitch = !(aFlags & FLAG_NOSWITCHFRAME) ||
                             IsSameOrAncestor(newWindow, mFocusedWindow);
   // if the element is in the active window, frame switching is allowed and
   // the content is in a visible window, fire blur and focus events.
   bool sendFocusEvent =
     isElementInActiveWindow && allowFrameSwitch && IsWindowVisible(newWindow);
   // When the following conditions are true:
   //  * an element has focus
   //  * isn't called by trusted event (i.e., called by untrusted event or by js)
   //  * the focus is moved to another document's element
   // we need to check the permission.
   if (sendFocusEvent && mFocusedContent &&
       mFocusedContent->OwnerDoc() != aNewContent->OwnerDoc()) {
     // If the caller cannot access the current focused node, the caller should
     // not be able to steal focus from it. E.g., When the current focused node
     // is in chrome, any web contents should not be able to steal the focus.
     nsCOMPtr<nsIDOMNode> domNode(do_QueryInterface(mFocusedContent));
     sendFocusEvent = nsContentUtils::CanCallerAccess(domNode);
     if (!sendFocusEvent && mMouseDownEventHandlingDocument) {
       // However, while mouse down event is handling, the handling document's
       // script should be able to steal focus.
       domNode = do_QueryInterface(mMouseDownEventHandlingDocument);
       sendFocusEvent = nsContentUtils::CanCallerAccess(domNode);
     }
   }
   LOGCONTENT("Shift Focus: %s", contentToFocus.get());
   LOGFOCUS((" Flags: %x Current Window: %p New Window: %p Current Element: %p",
            aFlags, mFocusedWindow.get(), newWindow.get(), mFocusedContent.get()));
   LOGFOCUS((" In Active Window: %d In Focused Window: %d SendFocus: %d",
            isElementInActiveWindow, isElementInFocusedWindow, sendFocusEvent));
   if (sendFocusEvent) {
     // return if blurring fails or the focus changes during the blur
     if (mFocusedWindow) {
       // if the focus is being moved to another element in the same document,
       // or to a descendant, pass the existing window to Blur so that the
       // current node in the existing window is cleared. If moving to a
       // window elsewhere, we want to maintain the current node in the
       // window but still blur it.
       bool currentIsSameOrAncestor = IsSameOrAncestor(mFocusedWindow, newWindow);
       // find the common ancestor of the currently focused window and the new
       // window. The ancestor will need to have its currently focused node
       // cleared once the document has been blurred. Otherwise, we'll be in a
       // state where a document is blurred yet the chain of windows above it
       // still points to that document.
       // For instance, in the following frame tree:
       //   A
       //  B C
       //  D
       // D is focused and we want to focus C. Once D has been blurred, we need
       // to clear out the focus in A, otherwise A would still maintain that B
       // was focused, and B that D was focused.
       nsCOMPtr<nsPIDOMWindow> commonAncestor;
       if (!isElementInFocusedWindow)
         commonAncestor = GetCommonAncestor(newWindow, mFocusedWindow);
       if (!Blur(currentIsSameOrAncestor ? mFocusedWindow.get() : nullptr,
                 commonAncestor, !isElementInFocusedWindow, aAdjustWidget))
         return;
     }
     Focus(newWindow, contentToFocus, aFlags, !isElementInFocusedWindow,
           aFocusChanged, false, aAdjustWidget);
   }
   else {
     // otherwise, for inactive windows and when the caller cannot steal the
     // focus, update the node in the window, and  raise the window if desired.
     if (allowFrameSwitch)
       AdjustWindowFocus(newWindow, true);
     // set the focus node and method as needed
     uint32_t focusMethod = aFocusChanged ? aFlags & FOCUSMETHODANDRING_MASK :
                            newWindow->GetFocusMethod() | (aFlags & FLAG_SHOWRING);
     newWindow->SetFocusedNode(contentToFocus, focusMethod);
     if (aFocusChanged) {
       nsCOMPtr<nsIDocShell> docShell = newWindow->GetDocShell();
       nsCOMPtr<nsIPresShell> presShell = docShell->GetPresShell();
       if (presShell)
         ScrollIntoView(presShell, contentToFocus, aFlags);
     }
     // update the commands even when inactive so that the attributes for that
     // window are up to date.
     if (allowFrameSwitch)
       newWindow->UpdateCommands(NS_LITERAL_STRING("focus"));
     if (aFlags & FLAG_RAISE)
       RaiseWindow(newRootWindow);
   }
 }
 bool
 nsFocusManager::IsSameOrAncestor(nsPIDOMWindow* aPossibleAncestor,
                                  nsPIDOMWindow* aWindow)
 {
   nsCOMPtr<nsIWebNavigation> awebnav(do_GetInterface(aPossibleAncestor));
   nsCOMPtr<nsIDocShellTreeItem> ancestordsti = do_QueryInterface(awebnav);
   nsCOMPtr<nsIWebNavigation> fwebnav(do_GetInterface(aWindow));
   nsCOMPtr<nsIDocShellTreeItem> dsti = do_QueryInterface(fwebnav);
   while (dsti) {
     if (dsti == ancestordsti)
       return true;
     nsCOMPtr<nsIDocShellTreeItem> parentDsti;
     dsti->GetParent(getter_AddRefs(parentDsti));
     dsti.swap(parentDsti);
   }
   return false;
 }
 already_AddRefed<nsPIDOMWindow>
 nsFocusManager::GetCommonAncestor(nsPIDOMWindow* aWindow1,
                                   nsPIDOMWindow* aWindow2)
 {
   nsCOMPtr<nsIWebNavigation> webnav(do_GetInterface(aWindow1));
   nsCOMPtr<nsIDocShellTreeItem> dsti1 = do_QueryInterface(webnav);
   NS_ENSURE_TRUE(dsti1, nullptr);
   webnav = do_GetInterface(aWindow2);
   nsCOMPtr<nsIDocShellTreeItem> dsti2 = do_QueryInterface(webnav);
   NS_ENSURE_TRUE(dsti2, nullptr);
   nsAutoTArray<nsIDocShellTreeItem*, 30> parents1, parents2;
   do {
     parents1.AppendElement(dsti1);
     nsCOMPtr<nsIDocShellTreeItem> parentDsti1;
     dsti1->GetParent(getter_AddRefs(parentDsti1));
     dsti1.swap(parentDsti1);
   } while (dsti1);
   do {
     parents2.AppendElement(dsti2);
     nsCOMPtr<nsIDocShellTreeItem> parentDsti2;
     dsti2->GetParent(getter_AddRefs(parentDsti2));
     dsti2.swap(parentDsti2);
   } while (dsti2);
   uint32_t pos1 = parents1.Length();
   uint32_t pos2 = parents2.Length();
   nsIDocShellTreeItem* parent = nullptr;
   uint32_t len;
   for (len = std::min(pos1, pos2); len > 0; --len) {
     nsIDocShellTreeItem* child1 = parents1.ElementAt(--pos1);
     nsIDocShellTreeItem* child2 = parents2.ElementAt(--pos2);
     if (child1 != child2) {
       break;
     }
     parent = child1;
   }
   nsCOMPtr<nsPIDOMWindow> window = do_GetInterface(parent);
   return window.forget();
 }
 void
 nsFocusManager::AdjustWindowFocus(nsPIDOMWindow* aWindow,
                                   bool aCheckPermission)
 {
   bool isVisible = IsWindowVisible(aWindow);
   nsCOMPtr<nsPIDOMWindow> window(aWindow);
   while (window) {
     // get the containing <iframe> or equivalent element so that it can be
     // focused below.
     nsCOMPtr<nsIContent> frameContent =
       do_QueryInterface(window->GetFrameElementInternal());
     nsCOMPtr<nsIWebNavigation> webnav(do_GetInterface(window));
     nsCOMPtr<nsIDocShellTreeItem> dsti = do_QueryInterface(webnav);
     if (!dsti)
       return;
     nsCOMPtr<nsIDocShellTreeItem> parentDsti;
     dsti->GetParent(getter_AddRefs(parentDsti));
     window = do_GetInterface(parentDsti);
     if (window) {
       // if the parent window is visible but aWindow was not, then we have
       // likely moved up and out from a hidden tab to the browser window, or a
       // similar such arrangement. Stop adjusting the current nodes.
       if (IsWindowVisible(window) != isVisible)
         break;
       // When aCheckPermission is true, we should check whether the caller can
       // access the window or not.  If it cannot access, we should stop the
       // adjusting.
       if (aCheckPermission && !nsContentUtils::CanCallerAccess(window))
         break;
       window->SetFocusedNode(frameContent);
     }
   }
 }
 bool
 nsFocusManager::IsWindowVisible(nsPIDOMWindow* aWindow)
 {
   if (!aWindow || aWindow->IsFrozen())
     return false;
   // Check if the inner window is frozen as well. This can happen when a focus change
   // occurs while restoring a previous page.
   nsPIDOMWindow* innerWindow = aWindow->GetCurrentInnerWindow();
   if (!innerWindow || innerWindow->IsFrozen())
     return false;
   nsCOMPtr<nsIDocShell> docShell = aWindow->GetDocShell();
   nsCOMPtr<nsIBaseWindow> baseWin(do_QueryInterface(docShell));
   if (!baseWin)
     return false;
   bool visible = false;
   baseWin->GetVisibility(&visible);
   return visible;
 }
 bool
 nsFocusManager::IsNonFocusableRoot(nsIContent* aContent)
 {
   NS_PRECONDITION(aContent, "aContent must not be NULL");
   NS_PRECONDITION(aContent->IsInDoc(), "aContent must be in a document");
   // If aContent is in designMode, the root element is not focusable.
   // NOTE: in designMode, most elements are not focusable, just the document is
   //       focusable.
   // Also, if aContent is not editable but it isn't in designMode, it's not
   // focusable.
   // And in userfocusignored context nothing is focusable.
   nsIDocument* doc = aContent->GetCurrentDoc();
   NS_ASSERTION(doc, "aContent must have current document");
   return aContent == doc->GetRootElement() &&
            (doc->HasFlag(NODE_IS_EDITABLE) || !aContent->IsEditable() ||
             nsContentUtils::IsUserFocusIgnored(aContent));
 }
 nsIContent*
 nsFocusManager::CheckIfFocusable(nsIContent* aContent, uint32_t aFlags)
 {
   if (!aContent)
     return nullptr;
   // this is a special case for some XUL elements where an anonymous child is
   // actually focusable and not the element itself.
   nsIContent* redirectedFocus = GetRedirectedFocus(aContent);
   if (redirectedFocus)
     return CheckIfFocusable(redirectedFocus, aFlags);
   nsCOMPtr<nsIDocument> doc = aContent->GetCurrentDoc();
   // can't focus elements that are not in documents
   if (!doc) {
     LOGCONTENT("Cannot focus %s because content not in document", aContent)
     return nullptr;
   }
   // Make sure that our frames are up to date
   doc->FlushPendingNotifications(Flush_Layout);
   nsIPresShell *shell = doc->GetShell();
   if (!shell)
     return nullptr;
   // the root content can always be focused,
   // except in userfocusignored context.
   if (aContent == doc->GetRootElement())
     return nsContentUtils::IsUserFocusIgnored(aContent) ? nullptr : aContent;
   // cannot focus content in print preview mode. Only the root can be focused.
   nsPresContext* presContext = shell->GetPresContext();
   if (presContext && presContext->Type() == nsPresContext::eContext_PrintPreview) {
     LOGCONTENT("Cannot focus %s while in print preview", aContent)
     return nullptr;
   }
   nsIFrame* frame = aContent->GetPrimaryFrame();
   if (!frame) {
     LOGCONTENT("Cannot focus %s as it has no frame", aContent)
     return nullptr;
   }
   if (aContent->Tag() == nsGkAtoms::area && aContent->IsHTML()) {
     // HTML areas do not have their own frame, and the img frame we get from
     // GetPrimaryFrame() is not relevant as to whether it is focusable or
     // not, so we have to do all the relevant checks manually for them.
     return frame->IsVisibleConsideringAncestors() &&
            aContent->IsFocusable() ? aContent : nullptr;
   }
   // if this is a child frame content node, check if it is visible and
   // call the content node's IsFocusable method instead of the frame's
   // IsFocusable method. This skips checking the style system and ensures that
   // offscreen browsers can still be focused.
   nsIDocument* subdoc = doc->GetSubDocumentFor(aContent);
   if (subdoc && IsWindowVisible(subdoc->GetWindow())) {
     const nsStyleUserInterface* ui = frame->StyleUserInterface();
     int32_t tabIndex = (ui->mUserFocus == NS_STYLE_USER_FOCUS_IGNORE ||
                         ui->mUserFocus == NS_STYLE_USER_FOCUS_NONE) ? -1 : 0;
     return aContent->IsFocusable(&tabIndex, aFlags & FLAG_BYMOUSE) ? aContent : nullptr;
   }
   return frame->IsFocusable(nullptr, aFlags & FLAG_BYMOUSE) ? aContent : nullptr;
 }
 bool
 nsFocusManager::Blur(nsPIDOMWindow* aWindowToClear,
                      nsPIDOMWindow* aAncestorWindowToFocus,
                      bool aIsLeavingDocument,
                      bool aAdjustWidgets)
 {
   LOGFOCUS(("<<Blur begin>>"));
   // hold a reference to the focused content, which may be null
   nsCOMPtr<nsIContent> content = mFocusedContent;
   if (content) {
     if (!content->IsInDoc()) {
       mFocusedContent = nullptr;
       return true;
     }
     if (content == mFirstBlurEvent)
       return true;
   }
   // hold a reference to the focused window
   nsCOMPtr<nsPIDOMWindow> window = mFocusedWindow;
   if (!window) {
     mFocusedContent = nullptr;
     return true;
   }
   nsCOMPtr<nsIDocShell> docShell = window->GetDocShell();
   if (!docShell) {
     mFocusedContent = nullptr;
     return true;
   }
   // Keep a ref to presShell since dispatching the DOM event may cause
   // the document to be destroyed.
   nsCOMPtr<nsIPresShell> presShell = docShell->GetPresShell();
   if (!presShell) {
     mFocusedContent = nullptr;
     return true;
   }
   bool clearFirstBlurEvent = false;
   if (!mFirstBlurEvent) {
     mFirstBlurEvent = content;
     clearFirstBlurEvent = true;
   }
   nsPresContext* focusedPresContext =
     mActiveWindow ? presShell->GetPresContext() : nullptr;
   IMEStateManager::OnChangeFocus(focusedPresContext, nullptr,
                                  GetFocusMoveActionCause(0));
   // now adjust the actual focus, by clearing the fields in the focus manager
   // and in the window.
   mFocusedContent = nullptr;
   bool shouldShowFocusRing = window->ShouldShowFocusRing();
   if (aWindowToClear)
     aWindowToClear->SetFocusedNode(nullptr);
   LOGCONTENT("Element %s has been blurred", content.get());
   // Don't fire blur event on the root content which isn't editable.
   bool sendBlurEvent =
     content && content->IsInDoc() && !IsNonFocusableRoot(content);
   if (content) {
     if (sendBlurEvent) {
       NotifyFocusStateChange(content, shouldShowFocusRing, false);
     }
     // if an object/plug-in/remote browser is being blurred, move the system focus
     // to the parent window, otherwise events will still get fired at the plugin.
     // But don't do this if we are blurring due to the window being lowered,
     // otherwise, the parent window can get raised again.
     if (mActiveWindow) {
       nsIFrame* contentFrame = content->GetPrimaryFrame();
       nsIObjectFrame* objectFrame = do_QueryFrame(contentFrame);
       if (aAdjustWidgets && objectFrame && !sTestMode) {
         // note that the presshell's widget is being retrieved here, not the one
         // for the object frame.
         nsViewManager* vm = presShell->GetViewManager();
         if (vm) {
           nsCOMPtr<nsIWidget> widget;
           vm->GetRootWidget(getter_AddRefs(widget));
           if (widget)
             widget->SetFocus(false);
         }
       }
       // if the object being blurred is a remote browser, deactivate remote content
       if (TabParent* remote = TabParent::GetFrom(content)) {
         remote->Deactivate();
         LOGFOCUS(("Remote browser deactivated"));
       }
     }
   }
   bool result = true;
   if (sendBlurEvent) {
     // if there is an active window, update commands. If there isn't an active
     // window, then this was a blur caused by the active window being lowered,
     // so there is no need to update the commands
     if (mActiveWindow)
       window->UpdateCommands(NS_LITERAL_STRING("focus"));
     SendFocusOrBlurEvent(NS_BLUR_CONTENT, presShell,
                          content->GetCurrentDoc(), content, 1, false);
   }
   // if we are leaving the document or the window was lowered, make the caret
   // invisible.
   if (aIsLeavingDocument || !mActiveWindow)
     SetCaretVisible(presShell, false, nullptr);
   // at this point, it is expected that this window will be still be
   // focused, but the focused content will be null, as it was cleared before
   // the event. If this isn't the case, then something else was focused during
   // the blur event above and we should just return. However, if
   // aIsLeavingDocument is set, a new document is desired, so make sure to
   // blur the document and window.
   if (mFocusedWindow != window ||
       (mFocusedContent != nullptr && !aIsLeavingDocument)) {
     result = false;
   }
   else if (aIsLeavingDocument) {
     window->TakeFocus(false, 0);
     // clear the focus so that the ancestor frame hierarchy is in the correct
     // state. Pass true because aAncestorWindowToFocus is thought to be
     // focused at this point.
     if (aAncestorWindowToFocus)
       aAncestorWindowToFocus->SetFocusedNode(nullptr, 0, true);
     SetFocusedWindowInternal(nullptr);
     mFocusedContent = nullptr;
     // pass 1 for the focus method when calling SendFocusOrBlurEvent just so
     // that the check is made for suppressed documents. Check to ensure that
     // the document isn't null in case someone closed it during the blur above
     nsIDocument* doc = window->GetExtantDoc();
     if (doc)
       SendFocusOrBlurEvent(NS_BLUR_CONTENT, presShell, doc, doc, 1, false);
     if (mFocusedWindow == nullptr)
       SendFocusOrBlurEvent(NS_BLUR_CONTENT, presShell, doc, window, 1, false);
     // check if a different window was focused
     result = (mFocusedWindow == nullptr && mActiveWindow);
   }
   else if (mActiveWindow) {
     // Otherwise, the blur of the element without blurring the document
     // occurred normally. Call UpdateCaret to redisplay the caret at the right
     // location within the document. This is needed to ensure that the caret
     // used for caret browsing is made visible again when an input field is
     // blurred.
     UpdateCaret(false, true, nullptr);
   }
   if (clearFirstBlurEvent)
     mFirstBlurEvent = nullptr;
   return result;
 }
 void
 nsFocusManager::Focus(nsPIDOMWindow* aWindow,
                       nsIContent* aContent,
                       uint32_t aFlags,
                       bool aIsNewDocument,
                       bool aFocusChanged,
                       bool aWindowRaised,
                       bool aAdjustWidgets)
 {
   LOGFOCUS(("<<Focus begin>>"));
   if (!aWindow)
     return;
   if (aContent && (aContent == mFirstFocusEvent || aContent == mFirstBlurEvent))
     return;
   // Keep a reference to the presShell since dispatching the DOM event may
   // cause the document to be destroyed.
   nsCOMPtr<nsIDocShell> docShell = aWindow->GetDocShell();
   if (!docShell)
     return;
   nsCOMPtr<nsIPresShell> presShell = docShell->GetPresShell();
   if (!presShell)
     return;
   // If the focus actually changed, set the focus method (mouse, keyboard, etc).
   // Otherwise, just get the current focus method and use that. This ensures
   // that the method is set during the document and window focus events.
   uint32_t focusMethod = aFocusChanged ? aFlags & FOCUSMETHODANDRING_MASK :
                          aWindow->GetFocusMethod() | (aFlags & FLAG_SHOWRING);
   if (!IsWindowVisible(aWindow)) {
     // if the window isn't visible, for instance because it is a hidden tab,
     // update the current focus and scroll it into view but don't do anything else
     if (CheckIfFocusable(aContent, aFlags)) {
       aWindow->SetFocusedNode(aContent, focusMethod);
       if (aFocusChanged)
         ScrollIntoView(presShell, aContent, aFlags);
     }
     return;
   }
   bool clearFirstFocusEvent = false;
   if (!mFirstFocusEvent) {
     mFirstFocusEvent = aContent;
     clearFirstFocusEvent = true;
   }
 #ifdef PR_LOGGING
   LOGCONTENT("Element %s has been focused", aContent);
   if (PR_LOG_TEST(gFocusLog, PR_LOG_DEBUG)) {
     nsIDocument* docm = aWindow->GetExtantDoc();
     if (docm) {
       LOGCONTENT(" from %s", docm->GetRootElement());
     }
     LOGFOCUS((" [Newdoc: %d FocusChanged: %d Raised: %d Flags: %x]",
              aIsNewDocument, aFocusChanged, aWindowRaised, aFlags));
   }
 #endif
   if (aIsNewDocument) {
     // if this is a new document, update the parent chain of frames so that
     // focus can be traversed from the top level down to the newly focused
     // window.
     AdjustWindowFocus(aWindow, false);
     // Update the window touch registration to reflect the state of
     // the new document that got focus
     aWindow->UpdateTouchState();
   }
   // indicate that the window has taken focus.
   if (aWindow->TakeFocus(true, focusMethod))
     aIsNewDocument = true;
   SetFocusedWindowInternal(aWindow);
   // Update the system focus by focusing the root widget.  But avoid this
   // if 1) aAdjustWidgets is false or 2) aContent is a plugin that has its
   // own widget and is either already focused or is about to be focused.
   nsCOMPtr<nsIWidget> objectFrameWidget;
   if (aContent) {
     nsIFrame* contentFrame = aContent->GetPrimaryFrame();
     nsIObjectFrame* objectFrame = do_QueryFrame(contentFrame);
     if (objectFrame)
       objectFrameWidget = objectFrame->GetWidget();
   }
   if (aAdjustWidgets && !objectFrameWidget && !sTestMode) {
     nsViewManager* vm = presShell->GetViewManager();
     if (vm) {
       nsCOMPtr<nsIWidget> widget;
       vm->GetRootWidget(getter_AddRefs(widget));
       if (widget)
         widget->SetFocus(false);
     }
   }
   // if switching to a new document, first fire the focus event on the
   // document and then the window.
   if (aIsNewDocument) {
     nsIDocument* doc = aWindow->GetExtantDoc();
     // The focus change should be notified to IMEStateManager from here if
     // the focused content is a designMode editor since any content won't
     // receive focus event.
     if (doc && doc->HasFlag(NODE_IS_EDITABLE)) {
       IMEStateManager::OnChangeFocus(presShell->GetPresContext(), nullptr,
                                      GetFocusMoveActionCause(aFlags));
     }
     if (doc)
       SendFocusOrBlurEvent(NS_FOCUS_CONTENT, presShell, doc,
                            doc, aFlags & FOCUSMETHOD_MASK, aWindowRaised);
     if (mFocusedWindow == aWindow && mFocusedContent == nullptr)
       SendFocusOrBlurEvent(NS_FOCUS_CONTENT, presShell, doc,
                            aWindow, aFlags & FOCUSMETHOD_MASK, aWindowRaised);
   }
   // check to ensure that the element is still focusable, and that nothing
   // else was focused during the events above.
   if (CheckIfFocusable(aContent, aFlags) &&
       mFocusedWindow == aWindow && mFocusedContent == nullptr) {
     mFocusedContent = aContent;
     nsIContent* focusedNode = aWindow->GetFocusedNode();
     bool isRefocus = focusedNode && focusedNode->IsEqualNode(aContent);
     aWindow->SetFocusedNode(aContent, focusMethod);
     bool sendFocusEvent =
       aContent && aContent->IsInDoc() && !IsNonFocusableRoot(aContent);
     nsPresContext* presContext = presShell->GetPresContext();
     if (sendFocusEvent) {
       // if the focused element changed, scroll it into view
       if (aFocusChanged)
         ScrollIntoView(presShell, aContent, aFlags);
       NotifyFocusStateChange(aContent, aWindow->ShouldShowFocusRing(), true);
       // if this is an object/plug-in/remote browser, focus its widget.  Note that we might
       // no longer be in the same document, due to the events we fired above when
       // aIsNewDocument.
       if (presShell->GetDocument() == aContent->GetDocument()) {
         if (aAdjustWidgets && objectFrameWidget && !sTestMode)
           objectFrameWidget->SetFocus(false);
         // if the object being focused is a remote browser, activate remote content
         if (TabParent* remote = TabParent::GetFrom(aContent)) {
           remote->Activate();
           LOGFOCUS(("Remote browser activated"));
         }
       }
       IMEStateManager::OnChangeFocus(presContext, aContent,
                                      GetFocusMoveActionCause(aFlags));
       // as long as this focus wasn't because a window was raised, update the
       // commands
       // XXXndeakin P2 someone could adjust the focus during the update
       if (!aWindowRaised)
         aWindow->UpdateCommands(NS_LITERAL_STRING("focus"));
       SendFocusOrBlurEvent(NS_FOCUS_CONTENT, presShell,
                            aContent->GetCurrentDoc(),
                            aContent, aFlags & FOCUSMETHOD_MASK,
                            aWindowRaised, isRefocus);
     } else {
       IMEStateManager::OnChangeFocus(presContext, nullptr,
                                      GetFocusMoveActionCause(aFlags));
       if (!aWindowRaised) {
         aWindow->UpdateCommands(NS_LITERAL_STRING("focus"));
       }
     }
   }
   else {
     // If the window focus event (fired above when aIsNewDocument) caused
     // the plugin not to be focusable, update the system focus by focusing
     // the root widget.
     if (aAdjustWidgets && objectFrameWidget &&
         mFocusedWindow == aWindow && mFocusedContent == nullptr &&
         !sTestMode) {
       nsViewManager* vm = presShell->GetViewManager();
       if (vm) {
         nsCOMPtr<nsIWidget> widget;
         vm->GetRootWidget(getter_AddRefs(widget));
         if (widget)
           widget->SetFocus(false);
       }
     }
     nsPresContext* presContext = presShell->GetPresContext();
     IMEStateManager::OnChangeFocus(presContext, nullptr,
                                    GetFocusMoveActionCause(aFlags));
     if (!aWindowRaised)
       aWindow->UpdateCommands(NS_LITERAL_STRING("focus"));
   }
   // update the caret visibility and position to match the newly focused
   // element. However, don't update the position if this was a focus due to a
   // mouse click as the selection code would already have moved the caret as
   // needed. If this is a different document than was focused before, also
   // update the caret's visibility. If this is the same document, the caret
   // visibility should be the same as before so there is no need to update it.
   if (mFocusedContent == aContent)
     UpdateCaret(aFocusChanged && !(aFlags & FLAG_BYMOUSE), aIsNewDocument,
                 mFocusedContent);
   if (clearFirstFocusEvent)
     mFirstFocusEvent = nullptr;
 }
 class FocusBlurEvent : public nsRunnable
 {
 public:
   FocusBlurEvent(nsISupports* aTarget, uint32_t aType,
                  nsPresContext* aContext, bool aWindowRaised,
                  bool aIsRefocus)
   : mTarget(aTarget), mType(aType), mContext(aContext),
     mWindowRaised(aWindowRaised), mIsRefocus(aIsRefocus) {}
   NS_IMETHOD Run()
   {
     InternalFocusEvent event(true, mType);
     event.mFlags.mBubbles = false;
     event.fromRaise = mWindowRaised;
     event.isRefocus = mIsRefocus;
     return EventDispatcher::Dispatch(mTarget, mContext, &event);
   }
   nsCOMPtr<nsISupports>   mTarget;
   uint32_t                mType;
   nsRefPtr<nsPresContext> mContext;
   bool                    mWindowRaised;
   bool                    mIsRefocus;
 };
 void
 nsFocusManager::SendFocusOrBlurEvent(uint32_t aType,
                                      nsIPresShell* aPresShell,
                                      nsIDocument* aDocument,
                                      nsISupports* aTarget,
                                      uint32_t aFocusMethod,
                                      bool aWindowRaised,
                                      bool aIsRefocus)
 {
   NS_ASSERTION(aType == NS_FOCUS_CONTENT || aType == NS_BLUR_CONTENT,
                "Wrong event type for SendFocusOrBlurEvent");
   nsCOMPtr<EventTarget> eventTarget = do_QueryInterface(aTarget);
   nsCOMPtr<nsINode> n = do_QueryInterface(aTarget);
   if (!n) {
     nsCOMPtr<nsPIDOMWindow> win = do_QueryInterface(aTarget);
     n = win ? win->GetExtantDoc() : nullptr;
   }
   bool dontDispatchEvent = n && nsContentUtils::IsUserFocusIgnored(n);
   // for focus events, if this event was from a mouse or key and event
   // handling on the document is suppressed, queue the event and fire it
   // later. For blur events, a non-zero value would be set for aFocusMethod.
   if (aFocusMethod && !dontDispatchEvent &&
       aDocument && aDocument->EventHandlingSuppressed()) {
     // aFlags is always 0 when aWindowRaised is true so this won't be called
     // on a window raise.
     NS_ASSERTION(!aWindowRaised, "aWindowRaised should not be set");
     for (uint32_t i = mDelayedBlurFocusEvents.Length(); i > 0; --i) {
       // if this event was already queued, remove it and append it to the end
       if (mDelayedBlurFocusEvents[i - 1].mType == aType &&
           mDelayedBlurFocusEvents[i - 1].mPresShell == aPresShell &&
           mDelayedBlurFocusEvents[i - 1].mDocument == aDocument &&
           mDelayedBlurFocusEvents[i - 1].mTarget == eventTarget) {
         mDelayedBlurFocusEvents.RemoveElementAt(i - 1);
       }
     }
     mDelayedBlurFocusEvents.AppendElement(
       nsDelayedBlurOrFocusEvent(aType, aPresShell, aDocument, eventTarget));
     return;
   }
 #ifdef ACCESSIBILITY
   nsAccessibilityService* accService = GetAccService();
   if (accService) {
     if (aType == NS_FOCUS_CONTENT)
       accService->NotifyOfDOMFocus(aTarget);
     else
       accService->NotifyOfDOMBlur(aTarget);
   }
 #endif
   if (!dontDispatchEvent) {
     nsContentUtils::AddScriptRunner(
       new FocusBlurEvent(aTarget, aType, aPresShell->GetPresContext(),
                          aWindowRaised, aIsRefocus));
   }
 }
 void
 nsFocusManager::ScrollIntoView(nsIPresShell* aPresShell,
                                nsIContent* aContent,
                                uint32_t aFlags)
 {
   // if the noscroll flag isn't set, scroll the newly focused element into view
   if (!(aFlags & FLAG_NOSCROLL))
     aPresShell->ScrollContentIntoView(aContent,
                                       nsIPresShell::ScrollAxis(
                                         nsIPresShell::SCROLL_MINIMUM,
                                         nsIPresShell::SCROLL_IF_NOT_VISIBLE),
                                       nsIPresShell::ScrollAxis(
                                         nsIPresShell::SCROLL_MINIMUM,
                                         nsIPresShell::SCROLL_IF_NOT_VISIBLE),
                                       nsIPresShell::SCROLL_OVERFLOW_HIDDEN);
 }
 void
 nsFocusManager::RaiseWindow(nsPIDOMWindow* aWindow)
 {
   // don't raise windows that are already raised or are in the process of
   // being lowered
   if (!aWindow || aWindow == mActiveWindow || aWindow == mWindowBeingLowered)
     return;
   if (sTestMode) {
     // In test mode, emulate the existing window being lowered and the new
     // window being raised.
     if (mActiveWindow)
       WindowLowered(mActiveWindow);
     WindowRaised(aWindow);
     return;
   }
 #if defined(XP_WIN)
   // Windows would rather we focus the child widget, otherwise, the toplevel
   // widget will always end up being focused. Fortunately, focusing the child
   // widget will also have the effect of raising the window this widget is in.
   // But on other platforms, we can just focus the toplevel widget to raise
   // the window.
   nsCOMPtr<nsPIDOMWindow> childWindow;
   GetFocusedDescendant(aWindow, true, getter_AddRefs(childWindow));
   if (!childWindow)
     childWindow = aWindow;
   nsCOMPtr<nsIDocShell> docShell = aWindow->GetDocShell();
   if (!docShell)
     return;
   nsCOMPtr<nsIPresShell> presShell = docShell->GetPresShell();
   if (!presShell)
     return;
   nsViewManager* vm = presShell->GetViewManager();
   if (vm) {
     nsCOMPtr<nsIWidget> widget;
     vm->GetRootWidget(getter_AddRefs(widget));
     if (widget)
       widget->SetFocus(true);
   }
 #else
   nsCOMPtr<nsIWebNavigation> webnav = do_GetInterface(aWindow);
   nsCOMPtr<nsIBaseWindow> treeOwnerAsWin = do_QueryInterface(webnav);
   if (treeOwnerAsWin) {
     nsCOMPtr<nsIWidget> widget;
     treeOwnerAsWin->GetMainWidget(getter_AddRefs(widget));
     if (widget)
       widget->SetFocus(true);
   }
 #endif
 }
 void
 nsFocusManager::UpdateCaretForCaretBrowsingMode()
 {
   UpdateCaret(false, true, mFocusedContent);
 }
 void
 nsFocusManager::UpdateCaret(bool aMoveCaretToFocus,
                             bool aUpdateVisibility,
                             nsIContent* aContent)
 {
   LOGFOCUS(("Update Caret: %d %d", aMoveCaretToFocus, aUpdateVisibility));
   if (!mFocusedWindow)
     return;
   // this is called when a document is focused or when the caretbrowsing
   // preference is changed
   nsCOMPtr<nsIDocShell> focusedDocShell = mFocusedWindow->GetDocShell();
   nsCOMPtr<nsIDocShellTreeItem> dsti = do_QueryInterface(focusedDocShell);
   if (!dsti)
     return;
   if (dsti->ItemType() == nsIDocShellTreeItem::typeChrome) {
     return;  // Never browse with caret in chrome
   }
   bool browseWithCaret =
     Preferences::GetBool("accessibility.browsewithcaret");
   nsCOMPtr<nsIPresShell> presShell = focusedDocShell->GetPresShell();
   if (!presShell)
     return;
   // If this is an editable document which isn't contentEditable, or a
   // contentEditable document and the node to focus is contentEditable,
   // return, so that we don't mess with caret visibility.
   bool isEditable = false;
   focusedDocShell->GetEditable(&isEditable);
   if (isEditable) {
     nsCOMPtr<nsIHTMLDocument> doc =
       do_QueryInterface(presShell->GetDocument());
     bool isContentEditableDoc =
       doc && doc->GetEditingState() == nsIHTMLDocument::eContentEditable;
     bool isFocusEditable =
       aContent && aContent->HasFlag(NODE_IS_EDITABLE);
     if (!isContentEditableDoc || isFocusEditable)
       return;
   }
   if (!isEditable && aMoveCaretToFocus)
     MoveCaretToFocus(presShell, aContent);
   if (!aUpdateVisibility)
     return;
   // XXXndeakin this doesn't seem right. It should be checking for this only
   // on the nearest ancestor frame which is a chrome frame. But this is
   // what the existing code does, so just leave it for now.
   if (!browseWithCaret) {
     nsCOMPtr<nsIContent> docContent =
       do_QueryInterface(mFocusedWindow->GetFrameElementInternal());
     if (docContent)
       browseWithCaret = docContent->AttrValueIs(kNameSpaceID_None,
                                                 nsGkAtoms::showcaret,
                                                 NS_LITERAL_STRING("true"),
                                                 eCaseMatters);
   }
   SetCaretVisible(presShell, browseWithCaret, aContent);
 }
 void
 nsFocusManager::MoveCaretToFocus(nsIPresShell* aPresShell, nsIContent* aContent)
 {
   // domDoc is a document interface we can create a range with
   nsCOMPtr<nsIDOMDocument> domDoc = do_QueryInterface(aPresShell->GetDocument());
   if (domDoc) {
     nsRefPtr<nsFrameSelection> frameSelection = aPresShell->FrameSelection();
     nsCOMPtr<nsISelection> domSelection = frameSelection->
       GetSelection(nsISelectionController::SELECTION_NORMAL);
     if (domSelection) {
       nsCOMPtr<nsIDOMNode> currentFocusNode(do_QueryInterface(aContent));
       // First clear the selection. This way, if there is no currently focused
       // content, the selection will just be cleared.
       domSelection->RemoveAllRanges();
       if (currentFocusNode) {
         nsCOMPtr<nsIDOMRange> newRange;
         nsresult rv = domDoc->CreateRange(getter_AddRefs(newRange));
         if (NS_SUCCEEDED(rv)) {
           // Set the range to the start of the currently focused node
           // Make sure it's collapsed
           newRange->SelectNodeContents(currentFocusNode);
           nsCOMPtr<nsIDOMNode> firstChild;
           currentFocusNode->GetFirstChild(getter_AddRefs(firstChild));
           if (!firstChild ||
               aContent->IsNodeOfType(nsINode::eHTML_FORM_CONTROL)) {
             // If current focus node is a leaf, set range to before the
             // node by using the parent as a container.
             // This prevents it from appearing as selected.
             newRange->SetStartBefore(currentFocusNode);
             newRange->SetEndBefore(currentFocusNode);
           }
           domSelection->AddRange(newRange);
           domSelection->CollapseToStart();
         }
       }
     }
   }
 }
 nsresult
 nsFocusManager::SetCaretVisible(nsIPresShell* aPresShell,
                                 bool aVisible,
                                 nsIContent* aContent)
 {
   // When browsing with caret, make sure caret is visible after new focus
   // Return early if there is no caret. This can happen for the testcase
   // for bug 308025 where a window is closed in a blur handler.
   nsRefPtr<nsCaret> caret = aPresShell->GetCaret();
   if (!caret)
     return NS_OK;
   bool caretVisible = false;
   caret->GetCaretVisible(&caretVisible);
   if (!aVisible && !caretVisible)
     return NS_OK;
   nsRefPtr<nsFrameSelection> frameSelection;
   if (aContent) {
     NS_ASSERTION(aContent->GetDocument() == aPresShell->GetDocument(),
                  "Wrong document?");
     nsIFrame *focusFrame = aContent->GetPrimaryFrame();
     if (focusFrame)
       frameSelection = focusFrame->GetFrameSelection();
   }
   nsRefPtr<nsFrameSelection> docFrameSelection = aPresShell->FrameSelection();
   if (docFrameSelection && caret &&
      (frameSelection == docFrameSelection || !aContent)) {
     nsISelection* domSelection = docFrameSelection->
       GetSelection(nsISelectionController::SELECTION_NORMAL);
     if (domSelection) {
       // First, hide the caret to prevent attempting to show it in SetCaretDOMSelection
       caret->SetCaretVisible(false);
       // Caret must blink on non-editable elements
       caret->SetIgnoreUserModify(true);
       // Tell the caret which selection to use
       caret->SetCaretDOMSelection(domSelection);
       // In content, we need to set the caret. The only special case is edit
       // fields, which have a different frame selection from the document.
       // They will take care of making the caret visible themselves.
       nsCOMPtr<nsISelectionController> selCon(do_QueryInterface(aPresShell));
       if (!selCon)
         return NS_ERROR_FAILURE;
       selCon->SetCaretReadOnly(false);
       selCon->SetCaretEnabled(aVisible);
       caret->SetCaretVisible(aVisible);
     }
   }
   return NS_OK;
 }
 nsresult
 nsFocusManager::GetSelectionLocation(nsIDocument* aDocument,
                                      nsIPresShell* aPresShell,
                                      nsIContent **aStartContent,
                                      nsIContent **aEndContent)
 {
   *aStartContent = *aEndContent = nullptr;
   nsresult rv = NS_ERROR_FAILURE;
   nsPresContext* presContext = aPresShell->GetPresContext();
   NS_ASSERTION(presContext, "mPresContent is null!!");
   nsRefPtr<nsFrameSelection> frameSelection = aPresShell->FrameSelection();
   nsCOMPtr<nsISelection> domSelection;
   if (frameSelection) {
     domSelection = frameSelection->
       GetSelection(nsISelectionController::SELECTION_NORMAL);
   }
   nsCOMPtr<nsIDOMNode> startNode, endNode;
   bool isCollapsed = false;
   nsCOMPtr<nsIContent> startContent, endContent;
   int32_t startOffset = 0;
   if (domSelection) {
     domSelection->GetIsCollapsed(&isCollapsed);
     nsCOMPtr<nsIDOMRange> domRange;
     rv = domSelection->GetRangeAt(0, getter_AddRefs(domRange));
     if (domRange) {
       domRange->GetStartContainer(getter_AddRefs(startNode));
       domRange->GetEndContainer(getter_AddRefs(endNode));
       domRange->GetStartOffset(&startOffset);
       nsIContent *childContent = nullptr;
       startContent = do_QueryInterface(startNode);
       if (startContent && startContent->IsElement()) {
         NS_ASSERTION(startOffset >= 0, "Start offset cannot be negative");
         childContent = startContent->GetChildAt(startOffset);
         if (childContent) {
           startContent = childContent;
         }
       }
       endContent = do_QueryInterface(endNode);
       if (endContent && endContent->IsElement()) {
         int32_t endOffset = 0;
         domRange->GetEndOffset(&endOffset);
         NS_ASSERTION(endOffset >= 0, "End offset cannot be negative");
         childContent = endContent->GetChildAt(endOffset);
         if (childContent) {
           endContent = childContent;
         }
       }
     }
   }
   else {
     rv = NS_ERROR_INVALID_ARG;
   }
   nsIFrame *startFrame = nullptr;
   if (startContent) {
     startFrame = startContent->GetPrimaryFrame();
     if (isCollapsed) {
       // Next check to see if our caret is at the very end of a node
       // If so, the caret is actually sitting in front of the next
       // logical frame's primary node - so for this case we need to
       // change caretContent to that node.
       if (startContent->NodeType() == nsIDOMNode::TEXT_NODE) {
         nsAutoString nodeValue;
         startContent->AppendTextTo(nodeValue);
         bool isFormControl =
           startContent->IsNodeOfType(nsINode::eHTML_FORM_CONTROL);
         if (nodeValue.Length() == (uint32_t)startOffset && !isFormControl &&
             startContent != aDocument->GetRootElement()) {
           // Yes, indeed we were at the end of the last node
           nsCOMPtr<nsIFrameEnumerator> frameTraversal;
           nsresult rv = NS_NewFrameTraversal(getter_AddRefs(frameTraversal),
                                              presContext, startFrame,
                                              eLeaf,
                                              false, // aVisual
                                              false, // aLockInScrollView
                                              true      // aFollowOOFs
                                              );
           NS_ENSURE_SUCCESS(rv, rv);
           nsIFrame *newCaretFrame = nullptr;
           nsCOMPtr<nsIContent> newCaretContent = startContent;
           bool endOfSelectionInStartNode(startContent == endContent);
           do {
             // Continue getting the next frame until the primary content for the frame
             // we are on changes - we don't want to be stuck in the same place
             frameTraversal->Next();
             newCaretFrame = static_cast<nsIFrame*>(frameTraversal->CurrentItem());
             if (nullptr == newCaretFrame)
               break;
             newCaretContent = newCaretFrame->GetContent();
           } while (!newCaretContent || newCaretContent == startContent);
           if (newCaretFrame && newCaretContent) {
             // If the caret is exactly at the same position of the new frame,
             // then we can use the newCaretFrame and newCaretContent for our position
             nsRefPtr<nsCaret> caret = aPresShell->GetCaret();
             nsRect caretRect;
             nsIFrame *frame = caret->GetGeometry(domSelection, &caretRect);
             if (frame) {
               nsPoint caretWidgetOffset;
               nsIWidget *widget = frame->GetNearestWidget(caretWidgetOffset);
               caretRect.MoveBy(caretWidgetOffset);
               nsPoint newCaretOffset;
               nsIWidget *newCaretWidget = newCaretFrame->GetNearestWidget(newCaretOffset);
               if (widget == newCaretWidget && caretRect.y == newCaretOffset.y &&
                   caretRect.x == newCaretOffset.x) {
                 // The caret is at the start of the new element.
                 startFrame = newCaretFrame;
                 startContent = newCaretContent;
                 if (endOfSelectionInStartNode) {
                   endContent = newCaretContent; // Ensure end of selection is not before start
                 }
               }
             }
           }
         }
       }
     }
   }
   *aStartContent = startContent;
   *aEndContent = endContent;
   NS_IF_ADDREF(*aStartContent);
   NS_IF_ADDREF(*aEndContent);
   return rv;
 }
 nsresult
 nsFocusManager::DetermineElementToMoveFocus(nsPIDOMWindow* aWindow,
                                             nsIContent* aStartContent,
                                             int32_t aType, bool aNoParentTraversal,
                                             nsIContent** aNextContent)
 {
   *aNextContent = nullptr;
   nsCOMPtr<nsIDocShell> docShell = aWindow->GetDocShell();
   if (!docShell)
     return NS_OK;
   nsCOMPtr<nsIContent> startContent = aStartContent;
   if (!startContent && aType != MOVEFOCUS_CARET) {
     if (aType == MOVEFOCUS_FORWARDDOC || aType == MOVEFOCUS_BACKWARDDOC) {
       // When moving between documents, make sure to get the right
       // starting content in a descendant.
       nsCOMPtr<nsPIDOMWindow> focusedWindow;
       startContent = GetFocusedDescendant(aWindow, true, getter_AddRefs(focusedWindow));
     }
     else {
       startContent = aWindow->GetFocusedNode();
     }
   }
   nsCOMPtr<nsIDocument> doc;
   if (startContent)
     doc = startContent->GetCurrentDoc();
   else
     doc = aWindow->GetExtantDoc();
   if (!doc)
     return NS_OK;
   LookAndFeel::GetInt(LookAndFeel::eIntID_TabFocusModel,
                       &nsIContent::sTabFocusModel);
   if (aType == MOVEFOCUS_ROOT) {
     NS_IF_ADDREF(*aNextContent = GetRootForFocus(aWindow, doc, false, false));
     return NS_OK;
   }
   if (aType == MOVEFOCUS_FORWARDDOC) {
     NS_IF_ADDREF(*aNextContent = GetNextTabbableDocument(startContent, true));
     return NS_OK;
   }
   if (aType == MOVEFOCUS_BACKWARDDOC) {
     NS_IF_ADDREF(*aNextContent = GetNextTabbableDocument(startContent, false));
     return NS_OK;
   }
   nsIContent* rootContent = doc->GetRootElement();
   NS_ENSURE_TRUE(rootContent, NS_OK);
   nsIPresShell *presShell = doc->GetShell();
   NS_ENSURE_TRUE(presShell, NS_OK);
   if (aType == MOVEFOCUS_FIRST) {
     if (!aStartContent)
       startContent = rootContent;
     return GetNextTabbableContent(presShell, startContent,
                                   nullptr, startContent,
                                   true, 1, false, aNextContent);
   }
   if (aType == MOVEFOCUS_LAST) {
     if (!aStartContent)
       startContent = rootContent;
     return GetNextTabbableContent(presShell, startContent,
                                   nullptr, startContent,
                                   false, 0, false, aNextContent);
   }
   bool forward = (aType == MOVEFOCUS_FORWARD || aType == MOVEFOCUS_CARET);
   bool doNavigation = true;
   bool ignoreTabIndex = false;
   // when a popup is open, we want to ensure that tab navigation occurs only
   // within the most recently opened panel. If a popup is open, its frame will
   // be stored in popupFrame.
   nsIFrame* popupFrame = nullptr;
   int32_t tabIndex = forward ? 1 : 0;
   if (startContent) {
     nsIFrame* frame = startContent->GetPrimaryFrame();
     if (startContent->Tag() == nsGkAtoms::area &&
         startContent->IsHTML())
       startContent->IsFocusable(&tabIndex);
     else if (frame)
       frame->IsFocusable(&tabIndex, 0);
     else
       startContent->IsFocusable(&tabIndex);
     // if the current element isn't tabbable, ignore the tabindex and just
     // look for the next element. The root content won't have a tabindex
     // so just treat this as the beginning of the tab order.
     if (tabIndex < 0) {
       tabIndex = 1;
       if (startContent != rootContent)
         ignoreTabIndex = true;
     }
     // check if the focus is currently inside a popup. Elements such as the
     // autocomplete widget use the noautofocus attribute to allow the focus to
     // remain outside the popup when it is opened.
     if (frame) {
       popupFrame = nsLayoutUtils::GetClosestFrameOfType(frame,
                                                         nsGkAtoms::menuPopupFrame);
     }
     if (popupFrame) {
       // Don't navigate outside of a popup, so pretend that the
       // root content is the popup itself
       rootContent = popupFrame->GetContent();
       NS_ASSERTION(rootContent, "Popup frame doesn't have a content node");
     }
     else if (!forward) {
       // If focus moves backward and when current focused node is root
       // content or <body> element which is editable by contenteditable
       // attribute, focus should move to its parent document.
       if (startContent == rootContent) {
         doNavigation = false;
       } else {
         nsIDocument* doc = startContent->GetCurrentDoc();
         if (startContent ==
               nsLayoutUtils::GetEditableRootContentByContentEditable(doc)) {
           doNavigation = false;
         }
       }
     }
   }
   else {
 #ifdef MOZ_XUL
     if (aType != MOVEFOCUS_CARET) {
       // if there is no focus, yet a panel is open, focus the first item in
       // the panel
       nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
       if (pm)
         popupFrame = pm->GetTopPopup(ePopupTypePanel);
     }
 #endif
     if (popupFrame) {
       rootContent = popupFrame->GetContent();
       NS_ASSERTION(rootContent, "Popup frame doesn't have a content node");
       startContent = rootContent;
     }
     else {
       // Otherwise, for content shells, start from the location of the caret.
       if (docShell->ItemType() != nsIDocShellTreeItem::typeChrome) {
         nsCOMPtr<nsIContent> endSelectionContent;
         GetSelectionLocation(doc, presShell,
                              getter_AddRefs(startContent),
                              getter_AddRefs(endSelectionContent));
         // If the selection is on the rootContent, then there is no selection
         if (startContent == rootContent) {
           startContent = nullptr;
         }
         if (aType == MOVEFOCUS_CARET) {
           // GetFocusInSelection finds a focusable link near the caret.
           // If there is no start content though, don't do this to avoid
           // focusing something unexpected.
           if (startContent) {
             GetFocusInSelection(aWindow, startContent,
                                 endSelectionContent, aNextContent);
           }
           return NS_OK;
         }
         if (startContent) {
           // when starting from a selection, we always want to find the next or
           // previous element in the document. So the tabindex on elements
           // should be ignored.
           ignoreTabIndex = true;
         }
       }
       if (!startContent) {
         // otherwise, just use the root content as the starting point
         startContent = rootContent;
         NS_ENSURE_TRUE(startContent, NS_OK);
       }
     }
   }
   NS_ASSERTION(startContent, "starting content not set");
   // keep a reference to the starting content. If we find that again, it means
   // we've iterated around completely and we don't want to adjust the focus.
   // The skipOriginalContentCheck will be set to true only for the first time
   // GetNextTabbableContent is called. This ensures that we don't break out
   // when nothing is focused to start with. Specifically,
   // GetNextTabbableContent first checks the root content -- which happens to
   // be the same as the start content -- when nothing is focused and tabbing
   // forward. Without skipOriginalContentCheck set to true, we'd end up
   // returning right away and focusing nothing. Luckily, GetNextTabbableContent
   // will never wrap around on its own, and can only return the original
   // content when it is called a second time or later.
   bool skipOriginalContentCheck = true;
   nsIContent* originalStartContent = startContent;
   LOGCONTENTNAVIGATION("Focus Navigation Start Content %s", startContent.get());
   LOGFOCUSNAVIGATION(("  Tabindex: %d Ignore: %d", tabIndex, ignoreTabIndex));
   while (doc) {
     if (doNavigation) {
       nsCOMPtr<nsIContent> nextFocus;
       nsresult rv = GetNextTabbableContent(presShell, rootContent,
                                            skipOriginalContentCheck ? nullptr : originalStartContent,
                                            startContent, forward,
                                            tabIndex, ignoreTabIndex,
                                            getter_AddRefs(nextFocus));
       NS_ENSURE_SUCCESS(rv, rv);
       // found a content node to focus.
       if (nextFocus) {
         LOGCONTENTNAVIGATION("Next Content: %s", nextFocus.get());
         // as long as the found node was not the same as the starting node,
         // set it as the return value.
         if (nextFocus != originalStartContent)
           NS_ADDREF(*aNextContent = nextFocus);
         return NS_OK;
       }
       if (popupFrame) {
         // in a popup, so start again from the beginning of the popup. However,
         // if we already started at the beginning, then there isn't anything to
         // focus, so just return
         if (startContent != rootContent) {
           startContent = rootContent;
           tabIndex = forward ? 1 : 0;
           continue;
         }
         return NS_OK;
       }
     }
     doNavigation = true;
     skipOriginalContentCheck = false;
     ignoreTabIndex = false;
     if (aNoParentTraversal) {
       if (startContent == rootContent)
         return NS_OK;
       startContent = rootContent;
       tabIndex = forward ? 1 : 0;
       continue;
     }
     // reached the beginning or end of the document. Traverse up to the parent
     // document and try again.
     nsCOMPtr<nsIDocShellTreeItem> docShellParent;
     docShell->GetParent(getter_AddRefs(docShellParent));
     if (docShellParent) {
       // move up to the parent shell and try again from there.
       // first, get the frame element this window is inside.
       nsCOMPtr<nsPIDOMWindow> piWindow = do_GetInterface(docShell);
       NS_ENSURE_TRUE(piWindow, NS_ERROR_FAILURE);
       // Next, retrieve the parent docshell, document and presshell.
       docShell = do_QueryInterface(docShellParent);
       NS_ENSURE_TRUE(docShell, NS_ERROR_FAILURE);
       nsCOMPtr<nsPIDOMWindow> piParentWindow = do_GetInterface(docShellParent);
       NS_ENSURE_TRUE(piParentWindow, NS_ERROR_FAILURE);
       doc = piParentWindow->GetExtantDoc();
       NS_ENSURE_TRUE(doc, NS_ERROR_FAILURE);
       presShell = doc->GetShell();
       rootContent = doc->GetRootElement();
       startContent = do_QueryInterface(piWindow->GetFrameElementInternal());
       if (startContent) {
         nsIFrame* frame = startContent->GetPrimaryFrame();
         if (!frame)
           return NS_OK;
         frame->IsFocusable(&tabIndex, 0);
         if (tabIndex < 0) {
           tabIndex = 1;
           ignoreTabIndex = true;
         }
         // if the frame is inside a popup, make sure to scan only within the
         // popup. This handles the situation of tabbing amongst elements
         // inside an iframe which is itself inside a popup. Otherwise,
         // navigation would move outside the popup when tabbing outside the
         // iframe.
         popupFrame = nsLayoutUtils::GetClosestFrameOfType(frame,
                                                           nsGkAtoms::menuPopupFrame);
         if (popupFrame) {
           rootContent = popupFrame->GetContent();
           NS_ASSERTION(rootContent, "Popup frame doesn't have a content node");
         }
       }
       else {
         startContent = rootContent;
         tabIndex = forward ? 1 : 0;
       }
     }
     else {
       // no parent, so call the tree owner. This will tell the embedder that
       // it should take the focus.
       bool tookFocus;
       docShell->TabToTreeOwner(forward, &tookFocus);
       // if the tree owner, took the focus, blur the current content
       if (tookFocus) {
         nsCOMPtr<nsPIDOMWindow> window = do_GetInterface(docShell);
         if (window->GetFocusedNode() == mFocusedContent)
           Blur(mFocusedWindow, nullptr, true, true);
         else
           window->SetFocusedNode(nullptr);
         return NS_OK;
       }
       // reset the tab index and start again from the beginning or end
       startContent = rootContent;
       tabIndex = forward ? 1 : 0;
     }
     // wrapped all the way around and didn't find anything to move the focus
     // to, so just break out
     if (startContent == originalStartContent)
       break;
   }
   return NS_OK;
 }
 nsresult
 nsFocusManager::GetNextTabbableContent(nsIPresShell* aPresShell,
                                        nsIContent* aRootContent,
                                        nsIContent* aOriginalStartContent,
                                        nsIContent* aStartContent,
                                        bool aForward,
                                        int32_t aCurrentTabIndex,
                                        bool aIgnoreTabIndex,
                                        nsIContent** aResultContent)
 {
   *aResultContent = nullptr;
   nsCOMPtr<nsIContent> startContent = aStartContent;
   if (!startContent)
     return NS_OK;
   LOGCONTENTNAVIGATION("GetNextTabbable: %s", aStartContent);
   LOGFOCUSNAVIGATION(("  tabindex: %d", aCurrentTabIndex));
   nsPresContext* presContext = aPresShell->GetPresContext();
   bool getNextFrame = true;
   nsCOMPtr<nsIContent> iterStartContent = aStartContent;
   while (1) {
     nsIFrame* startFrame = iterStartContent->GetPrimaryFrame();
     // if there is no frame, look for another content node that has a frame
     if (!startFrame) {
       // if the root content doesn't have a frame, just return
       if (iterStartContent == aRootContent)
         return NS_OK;
       // look for the next or previous content node in tree order
       iterStartContent = aForward ? iterStartContent->GetNextNode() : iterStartContent->GetPreviousContent();
       // we've already skipped over the initial focused content, so we
       // don't want to traverse frames.
       getNextFrame = false;
       if (iterStartContent)
         continue;
       // otherwise, as a last attempt, just look at the root content
       iterStartContent = aRootContent;
       continue;
     }
     nsCOMPtr<nsIFrameEnumerator> frameTraversal;
     nsresult rv = NS_NewFrameTraversal(getter_AddRefs(frameTraversal),
                                        presContext, startFrame,
                                        ePreOrder,
                                        false, // aVisual
                                        false, // aLockInScrollView
                                        true      // aFollowOOFs
                                        );
     NS_ENSURE_SUCCESS(rv, rv);
     if (iterStartContent == aRootContent) {
       if (!aForward) {
         frameTraversal->Last();
       } else if (aRootContent->IsFocusable()) {
         frameTraversal->Next();
       }
     }
     else if (getNextFrame &&
              (!iterStartContent || iterStartContent->Tag() != nsGkAtoms::area ||
               !iterStartContent->IsHTML())) {
       // Need to do special check in case we're in an imagemap which has multiple
       // content nodes per frame, so don't skip over the starting frame.
       if (aForward)
         frameTraversal->Next();
       else
         frameTraversal->Prev();
     }
     // Walk frames to find something tabbable matching mCurrentTabIndex
     nsIFrame* frame = static_cast<nsIFrame*>(frameTraversal->CurrentItem());
     while (frame) {
       // TabIndex not set defaults to 0 for form elements, anchors and other
       // elements that are normally focusable. Tabindex defaults to -1
       // for elements that are not normally focusable.
       // The returned computed tabindex from IsFocusable() is as follows:
       //          < 0 not tabbable at all
       //          == 0 in normal tab order (last after positive tabindexed items)
       //          > 0 can be tabbed to in the order specified by this value
       int32_t tabIndex;
       frame->IsFocusable(&tabIndex, 0);
       LOGCONTENTNAVIGATION("Next Tabbable %s:", frame->GetContent());
       LOGFOCUSNAVIGATION(("  with tabindex: %d expected: %d", tabIndex, aCurrentTabIndex));
       nsIContent* currentContent = frame->GetContent();
       if (tabIndex >= 0) {
         NS_ASSERTION(currentContent, "IsFocusable set a tabindex for a frame with no content");
         if (currentContent->Tag() == nsGkAtoms::img &&
             currentContent->HasAttr(kNameSpaceID_None, nsGkAtoms::usemap)) {
           // This is an image with a map. Image map areas are not traversed by
           // nsIFrameTraversal so look for the next or previous area element.
           nsIContent *areaContent =
             GetNextTabbableMapArea(aForward, aCurrentTabIndex,
                                    currentContent, iterStartContent);
           if (areaContent) {
             NS_ADDREF(*aResultContent = areaContent);
             return NS_OK;
           }
         }
         else if (aIgnoreTabIndex || aCurrentTabIndex == tabIndex) {
           // break out if we've wrapped around to the start again.
           if (aOriginalStartContent && currentContent == aOriginalStartContent) {
             NS_ADDREF(*aResultContent = currentContent);
             return NS_OK;
           }
           // found a node with a matching tab index. Check if it is a child
           // frame. If so, navigate into the child frame instead.
           nsIDocument* doc = currentContent->GetCurrentDoc();
           NS_ASSERTION(doc, "content not in document");
           nsIDocument* subdoc = doc->GetSubDocumentFor(currentContent);
           if (subdoc) {
             if (!subdoc->EventHandlingSuppressed()) {
               if (aForward) {
                 // when tabbing forward into a frame, return the root
                 // frame so that the canvas becomes focused.
                 nsCOMPtr<nsPIDOMWindow> subframe = subdoc->GetWindow();
                 if (subframe) {
                   // If the subframe body is editable by contenteditable,
                   // we should set the editor's root element rather than the
                   // actual root element.  Otherwise, we should set the focus
                   // to the root content.
                   *aResultContent =
                     nsLayoutUtils::GetEditableRootContentByContentEditable(subdoc);
                   if (!*aResultContent ||
                       !((*aResultContent)->GetPrimaryFrame())) {
                     *aResultContent =
                       GetRootForFocus(subframe, subdoc, false, true);
                   }
                   if (*aResultContent) {
                     NS_ADDREF(*aResultContent);
                     return NS_OK;
                   }
                 }
               }
               Element* rootElement = subdoc->GetRootElement();
               nsIPresShell* subShell = subdoc->GetShell();
               if (rootElement && subShell) {
                 rv = GetNextTabbableContent(subShell, rootElement,
                                             aOriginalStartContent, rootElement,
                                             aForward, (aForward ? 1 : 0),
                                             false, aResultContent);
                 NS_ENSURE_SUCCESS(rv, rv);
                 if (*aResultContent)
                   return NS_OK;
               }
             }
           }
           // otherwise, use this as the next content node to tab to, unless
           // this was the element we started on. This would happen for
           // instance on an element with child frames, where frame navigation
           // could return the original element again. In that case, just skip
           // it. Also, if the next content node is the root content, then
           // return it. This latter case would happen only if someone made a
           // popup focusable.
           // Also, when going backwards, check to ensure that the focus
           // wouldn't be redirected. Otherwise, for example, when an input in
           // a textbox is focused, the enclosing textbox would be found and
           // the same inner input would be returned again.
           else if (currentContent == aRootContent ||
                    (currentContent != startContent &&
                     (aForward || !GetRedirectedFocus(currentContent)))) {
             NS_ADDREF(*aResultContent = currentContent);
             return NS_OK;
           }
         }
       }
       else if (aOriginalStartContent && currentContent == aOriginalStartContent) {
         // not focusable, so return if we have wrapped around to the original
         // content. This is necessary in case the original starting content was
         // not focusable.
         NS_ADDREF(*aResultContent = currentContent);
         return NS_OK;
       }
       // Move to the next or previous frame, but ignore continuation frames
       // since only the first frame should be involved in focusability.
       // Otherwise, a loop will occur in the following example:
       //   <span tabindex="1">...<a/><a/>...</span>
       // where the text wraps onto multiple lines. Tabbing from the second
       // link can find one of the span's continuation frames between the link
       // and the end of the span, and the span would end up getting focused
       // again.
       do {
         if (aForward)
           frameTraversal->Next();
         else
           frameTraversal->Prev();
         frame = static_cast<nsIFrame*>(frameTraversal->CurrentItem());
       } while (frame && frame->GetPrevContinuation());
     }
     // If already at lowest priority tab (0), end search completely.
     // A bit counterintuitive but true, tabindex order goes 1, 2, ... 32767, 0
     if (aCurrentTabIndex == (aForward ? 0 : 1)) {
       // if going backwards, the canvas should be focused once the beginning
       // has been reached.
       if (!aForward) {
         nsCOMPtr<nsPIDOMWindow> window = GetCurrentWindow(aRootContent);
         NS_ENSURE_TRUE(window, NS_ERROR_FAILURE);
         NS_IF_ADDREF(*aResultContent =
                      GetRootForFocus(window, aRootContent->GetCurrentDoc(), false, true));
       }
       break;
     }
     // continue looking for next highest priority tabindex
     aCurrentTabIndex = GetNextTabIndex(aRootContent, aCurrentTabIndex, aForward);
     startContent = iterStartContent = aRootContent;
   }
   return NS_OK;
 }
 nsIContent*
 nsFocusManager::GetNextTabbableMapArea(bool aForward,
                                        int32_t aCurrentTabIndex,
                                        nsIContent* aImageContent,
                                        nsIContent* aStartContent)
 {
   nsAutoString useMap;
   aImageContent->GetAttr(kNameSpaceID_None, nsGkAtoms::usemap, useMap);
   nsCOMPtr<nsIDocument> doc = aImageContent->GetDocument();
   if (doc) {
     nsCOMPtr<nsIContent> mapContent = doc->FindImageMap(useMap);
     if (!mapContent)
       return nullptr;
     uint32_t count = mapContent->GetChildCount();
     // First see if the the start content is in this map
     int32_t index = mapContent->IndexOf(aStartContent);
     int32_t tabIndex;
     if (index < 0 || (aStartContent->IsFocusable(&tabIndex) &&
                       tabIndex != aCurrentTabIndex)) {
       // If aStartContent is in this map we must start iterating past it.
       // We skip the case where aStartContent has tabindex == aStartContent
       // since the next tab ordered element might be before it
       // (or after for backwards) in the child list.
       index = aForward ? -1 : (int32_t)count;
     }
     // GetChildAt will return nullptr if our index < 0 or index >= count
     nsCOMPtr<nsIContent> areaContent;
     while ((areaContent = mapContent->GetChildAt(aForward ? ++index : --index)) != nullptr) {
       if (areaContent->IsFocusable(&tabIndex) && tabIndex == aCurrentTabIndex) {
         return areaContent;
       }
     }
   }
   return nullptr;
 }
 int32_t
 nsFocusManager::GetNextTabIndex(nsIContent* aParent,
                                 int32_t aCurrentTabIndex,
                                 bool aForward)
 {
   int32_t tabIndex, childTabIndex;
   if (aForward) {
     tabIndex = 0;
     for (nsIContent* child = aParent->GetFirstChild();
          child;
          child = child->GetNextSibling()) {
       childTabIndex = GetNextTabIndex(child, aCurrentTabIndex, aForward);
       if (childTabIndex > aCurrentTabIndex && childTabIndex != tabIndex) {
         tabIndex = (tabIndex == 0 || childTabIndex < tabIndex) ? childTabIndex : tabIndex;
       }
       nsAutoString tabIndexStr;
       child->GetAttr(kNameSpaceID_None, nsGkAtoms::tabindex, tabIndexStr);
       nsresult ec;
       int32_t val = tabIndexStr.ToInteger(&ec);
       if (NS_SUCCEEDED (ec) && val > aCurrentTabIndex && val != tabIndex) {
         tabIndex = (tabIndex == 0 || val < tabIndex) ? val : tabIndex;
       }
     }
   }
   else { /* !aForward */
     tabIndex = 1;
     for (nsIContent* child = aParent->GetFirstChild();
          child;
          child = child->GetNextSibling()) {
       childTabIndex = GetNextTabIndex(child, aCurrentTabIndex, aForward);
       if ((aCurrentTabIndex == 0 && childTabIndex > tabIndex) ||
           (childTabIndex < aCurrentTabIndex && childTabIndex > tabIndex)) {
         tabIndex = childTabIndex;
       }
       nsAutoString tabIndexStr;
       child->GetAttr(kNameSpaceID_None, nsGkAtoms::tabindex, tabIndexStr);
       nsresult ec;
       int32_t val = tabIndexStr.ToInteger(&ec);
       if (NS_SUCCEEDED (ec)) {
         if ((aCurrentTabIndex == 0 && val > tabIndex) ||
             (val < aCurrentTabIndex && val > tabIndex) ) {
           tabIndex = val;
         }
       }
     }
   }
   return tabIndex;
 }
 nsIContent*
 nsFocusManager::GetRootForFocus(nsPIDOMWindow* aWindow,
                                 nsIDocument* aDocument,
                                 bool aIsForDocNavigation,
                                 bool aCheckVisibility)
 {
   // the root element's canvas may be focused as long as the document is in a
   // a non-chrome shell and does not contain a frameset.
   if (aIsForDocNavigation) {
     nsCOMPtr<nsIContent> docContent =
       do_QueryInterface(aWindow->GetFrameElementInternal());
     // document navigation skips iframes and frames that are specifically non-focusable
     if (docContent) {
       if (docContent->Tag() == nsGkAtoms::iframe)
         return nullptr;
       nsIFrame* frame = docContent->GetPrimaryFrame();
       if (!frame || !frame->IsFocusable(nullptr, 0))
         return nullptr;
     }
   } else {
     nsCOMPtr<nsIDocShell> docShell = aWindow->GetDocShell();
     if (docShell->ItemType() == nsIDocShellTreeItem::typeChrome) {
       return nullptr;
     }
   }
   if (aCheckVisibility && !IsWindowVisible(aWindow))
     return nullptr;
   Element *rootElement = aDocument->GetRootElement();
   if (!rootElement) {
     return nullptr;
   }
   if (aCheckVisibility && !rootElement->GetPrimaryFrame()) {
     return nullptr;
   }
   // Finally, check if this is a frameset
   nsCOMPtr<nsIHTMLDocument> htmlDoc = do_QueryInterface(aDocument);
   if (htmlDoc && aDocument->GetHtmlChildElement(nsGkAtoms::frameset)) {
     return nullptr;
   }
   return rootElement;
 }
 void
 nsFocusManager::GetLastDocShell(nsIDocShellTreeItem* aItem,
                                 nsIDocShellTreeItem** aResult)
 {
   *aResult = nullptr;
   nsCOMPtr<nsIDocShellTreeItem> curItem = aItem;
   while (curItem) {
     int32_t childCount = 0;
     curItem->GetChildCount(&childCount);
     if (!childCount) {
       *aResult = curItem;
       NS_ADDREF(*aResult);
       return;
     }
     curItem->GetChildAt(childCount - 1, getter_AddRefs(curItem));
   }
 }
 void
 nsFocusManager::GetNextDocShell(nsIDocShellTreeItem* aItem,
                                 nsIDocShellTreeItem** aResult)
 {
   *aResult = nullptr;
   int32_t childCount = 0;
   aItem->GetChildCount(&childCount);
   if (childCount) {
     aItem->GetChildAt(0, aResult);
     if (*aResult)
       return;
   }
   nsCOMPtr<nsIDocShellTreeItem> curItem = aItem;
   while (curItem) {
     nsCOMPtr<nsIDocShellTreeItem> parentItem;
     curItem->GetParent(getter_AddRefs(parentItem));
     if (!parentItem)
       return;
     // Note that we avoid using GetChildOffset() here because docshell
     // child offsets can't be trusted to be correct. bug 162283.
     nsCOMPtr<nsIDocShellTreeItem> iterItem;
     childCount = 0;
     parentItem->GetChildCount(&childCount);
     for (int32_t index = 0; index < childCount; ++index) {
       parentItem->GetChildAt(index, getter_AddRefs(iterItem));
       if (iterItem == curItem) {
         ++index;
         if (index < childCount) {
           parentItem->GetChildAt(index, aResult);
           if (*aResult)
             return;
         }
         break;
       }
     }
     curItem = parentItem;
   }
 }
 void
 nsFocusManager::GetPreviousDocShell(nsIDocShellTreeItem* aItem,
                                     nsIDocShellTreeItem** aResult)
 {
   *aResult = nullptr;
   nsCOMPtr<nsIDocShellTreeItem> parentItem;
   aItem->GetParent(getter_AddRefs(parentItem));
   if (!parentItem)
     return;
   // Note that we avoid using GetChildOffset() here because docshell
   // child offsets can't be trusted to be correct. bug 162283.
   int32_t childCount = 0;
   parentItem->GetChildCount(&childCount);
   nsCOMPtr<nsIDocShellTreeItem> prevItem, iterItem;
   for (int32_t index = 0; index < childCount; ++index) {
     parentItem->GetChildAt(index, getter_AddRefs(iterItem));
     if (iterItem == aItem)
       break;
     prevItem = iterItem;
   }
   if (prevItem)
     GetLastDocShell(prevItem, aResult);
   else
     NS_ADDREF(*aResult = parentItem);
 }
 nsIContent*
 nsFocusManager::GetNextTabbablePanel(nsIDocument* aDocument, nsIFrame* aCurrentPopup, bool aForward)
 {
   nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
   if (!pm)
     return nullptr;
   // Iterate through the array backwards if aForward is false.
   nsTArray<nsIFrame *> popups;
   pm->GetVisiblePopups(popups);
   int32_t i = aForward ? 0 : popups.Length() - 1;
   int32_t end = aForward ? popups.Length() : -1;
   for (; i != end; aForward ? i++ : i--) {
     nsIFrame* popupFrame = popups[i];
     if (aCurrentPopup) {
       // If the current popup is set, then we need to skip over this popup and
       // wait until the currently focused popup is found. Once found, the
       // current popup will be cleared so that the next popup is used.
       if (aCurrentPopup == popupFrame)
         aCurrentPopup = nullptr;
       continue;
     }
     // Skip over non-panels
     if (popupFrame->GetContent()->Tag() != nsGkAtoms::panel ||
         (aDocument && popupFrame->GetContent()->GetCurrentDoc() != aDocument)) {
       continue;
     }
     // Find the first focusable content within the popup. If there isn't any
     // focusable content in the popup, skip to the next popup.
     nsIPresShell* presShell = popupFrame->PresContext()->GetPresShell();
     if (presShell) {
       nsCOMPtr<nsIContent> nextFocus;
       nsIContent* popup = popupFrame->GetContent();
       nsresult rv = GetNextTabbableContent(presShell, popup,
                                            nullptr, popup,
                                            true, 1, false,
                                            getter_AddRefs(nextFocus));
       if (NS_SUCCEEDED(rv) && nextFocus) {
         return nextFocus.get();
       }
     }
   }
   return nullptr;
 }
 nsIContent*
 nsFocusManager::GetNextTabbableDocument(nsIContent* aStartContent, bool aForward)
 {
   // If currentPopup is set, then the starting content is in a panel.
   nsIFrame* currentPopup = nullptr;
   nsCOMPtr<nsIDocument> doc;
   nsCOMPtr<nsIDocShell> startDocShell;
   if (aStartContent) {
     doc = aStartContent->GetCurrentDoc();
     if (doc) {
       startDocShell = doc->GetWindow()->GetDocShell();
     }
     // Check if the starting content is inside a panel. Document navigation
     // must start from this panel instead of the document root.
     nsIContent* content = aStartContent;
     while (content) {
       if (content->NodeInfo()->Equals(nsGkAtoms::panel, kNameSpaceID_XUL)) {
         currentPopup = content->GetPrimaryFrame();
         break;
       }
       content = content->GetParent();
     }
   }
   else if (mFocusedWindow) {
     startDocShell = mFocusedWindow->GetDocShell();
     doc = mFocusedWindow->GetExtantDoc();
   }
   else {
     nsCOMPtr<nsIWebNavigation> webnav = do_GetInterface(mActiveWindow);
     startDocShell = do_QueryInterface(webnav);
     if (mActiveWindow) {
       doc = mActiveWindow->GetExtantDoc();
     }
   }
   if (!startDocShell)
     return nullptr;
   // perform a depth first search (preorder) of the docshell tree
   // looking for an HTML Frame or a chrome document
   nsIContent* content = aStartContent;
   nsCOMPtr<nsIDocShellTreeItem> curItem = startDocShell.get();
   nsCOMPtr<nsIDocShellTreeItem> nextItem;
   do {
     // If moving forward, check for a panel in the starting document. If one
     // exists with focusable content, return that content instead of the next
     // document. If currentPopup is set, then, another panel may exist. If no
     // such panel exists, then continue on to check the next document.
     // When moving backwards, and the starting content is in a panel, then
     // check for additional panels in the starting document. If the starting
     // content is not in a panel, move back to the previous document and check
     // for panels there.
     bool checkPopups = false;
     nsCOMPtr<nsPIDOMWindow> nextFrame = nullptr;
     if (doc && (aForward || currentPopup)) {
       nsIContent* popupContent = GetNextTabbablePanel(doc, currentPopup, aForward);
       if (popupContent)
         return popupContent;
       if (!aForward && currentPopup) {
         // The starting content was in a popup, yet no other popups were
         // found. Move onto the starting content's document.
         nextFrame = doc->GetWindow();
       }
     }
     // Look for the next or previous document.
     if (!nextFrame) {
       if (aForward) {
         GetNextDocShell(curItem, getter_AddRefs(nextItem));
         if (!nextItem) {
           // wrap around to the beginning, which is the top of the tree
           startDocShell->GetRootTreeItem(getter_AddRefs(nextItem));
         }
       }
       else {
         GetPreviousDocShell(curItem, getter_AddRefs(nextItem));
         if (!nextItem) {
           // wrap around to the end, which is the last item in the tree
           nsCOMPtr<nsIDocShellTreeItem> rootItem;
           startDocShell->GetRootTreeItem(getter_AddRefs(rootItem));
           GetLastDocShell(rootItem, getter_AddRefs(nextItem));
         }
         // When going back to the previous document, check for any focusable
         // popups in that previous document first.
         checkPopups = true;
       }
       curItem = nextItem;
       nextFrame = do_GetInterface(nextItem);
     }
     if (!nextFrame)
       return nullptr;
     // Clear currentPopup for the next iteration
     currentPopup = nullptr;
     // If event handling is suppressed, move on to the next document. Set
     // content to null so that the popup check will be skipped on the next
     // loop iteration.
     doc = nextFrame->GetExtantDoc();
     if (!doc || doc->EventHandlingSuppressed()) {
       content = nullptr;
       continue;
     }
     if (checkPopups) {
       // When iterating backwards, check the panels of the previous document
       // first. If a panel exists that has focusable content, focus that.
       // Otherwise, continue on to focus the document.
       nsIContent* popupContent = GetNextTabbablePanel(doc, nullptr, false);
       if (popupContent)
         return popupContent;
     }
     content = GetRootForFocus(nextFrame, doc, true, true);
     if (content && !GetRootForFocus(nextFrame, doc, false, false)) {
       // if the found content is in a chrome shell or a frameset, navigate
       // forward one tabbable item so that the first item is focused. Note
       // that we always go forward and not back here.
       nsCOMPtr<nsIContent> nextFocus;
       Element* rootElement = doc->GetRootElement();
       nsIPresShell* presShell = doc->GetShell();
       if (presShell) {
         nsresult rv = GetNextTabbableContent(presShell, rootElement,
                                              nullptr, rootElement,
                                              true, 1, false,
                                              getter_AddRefs(nextFocus));
         return NS_SUCCEEDED(rv) ? nextFocus.get() : nullptr;
       }
     }
   } while (!content);
   return content;
 }
 void
 nsFocusManager::GetFocusInSelection(nsPIDOMWindow* aWindow,
                                     nsIContent* aStartSelection,
                                     nsIContent* aEndSelection,
                                     nsIContent** aFocusedContent)
 {
   *aFocusedContent = nullptr;
   nsCOMPtr<nsIContent> testContent = aStartSelection;
   nsCOMPtr<nsIContent> nextTestContent = aEndSelection;
   nsCOMPtr<nsIContent> currentFocus = aWindow->GetFocusedNode();
   // We now have the correct start node in selectionContent!
   // Search for focusable elements, starting with selectionContent
   // Method #1: Keep going up while we look - an ancestor might be focusable
   // We could end the loop earlier, such as when we're no longer
   // in the same frame, by comparing selectionContent->GetPrimaryFrame()
   // with a variable holding the starting selectionContent
   while (testContent) {
     // Keep testing while selectionContent is equal to something,
     // eventually we'll run out of ancestors
     nsCOMPtr<nsIURI> uri;
     if (testContent == currentFocus ||
         testContent->IsLink(getter_AddRefs(uri))) {
       NS_ADDREF(*aFocusedContent = testContent);
       return;
     }
     // Get the parent
     testContent = testContent->GetParent();
     if (!testContent) {
       // We run this loop again, checking the ancestor chain of the selection's end point
       testContent = nextTestContent;
       nextTestContent = nullptr;
     }
   }
   // We couldn't find an anchor that was an ancestor of the selection start
   // Method #2: look for anchor in selection's primary range (depth first search)
   // Turn into nodes so that we can use GetNextSibling() and GetFirstChild()
   nsCOMPtr<nsIDOMNode> selectionNode(do_QueryInterface(aStartSelection));
   nsCOMPtr<nsIDOMNode> endSelectionNode(do_QueryInterface(aEndSelection));
   nsCOMPtr<nsIDOMNode> testNode;
   do {
     testContent = do_QueryInterface(selectionNode);
     // We're looking for any focusable link that could be part of the
     // main document's selection.
     nsCOMPtr<nsIURI> uri;
     if (testContent == currentFocus ||
         testContent->IsLink(getter_AddRefs(uri))) {
       NS_ADDREF(*aFocusedContent = testContent);
       return;
     }
     selectionNode->GetFirstChild(getter_AddRefs(testNode));
     if (testNode) {
       selectionNode = testNode;
       continue;
     }
     if (selectionNode == endSelectionNode)
       break;
     selectionNode->GetNextSibling(getter_AddRefs(testNode));
     if (testNode) {
       selectionNode = testNode;
       continue;
     }
     do {
       selectionNode->GetParentNode(getter_AddRefs(testNode));
       if (!testNode || testNode == endSelectionNode) {
         selectionNode = nullptr;
         break;
       }
       testNode->GetNextSibling(getter_AddRefs(selectionNode));
       if (selectionNode)
         break;
       selectionNode = testNode;
     } while (true);
   }
   while (selectionNode && selectionNode != endSelectionNode);
 }
 class PointerUnlocker : public nsRunnable
 {
 public:
   PointerUnlocker()
   {
     MOZ_ASSERT(!PointerUnlocker::sActiveUnlocker);
     PointerUnlocker::sActiveUnlocker = this;
   }
   ~PointerUnlocker()
   {
     if (PointerUnlocker::sActiveUnlocker == this) {
       PointerUnlocker::sActiveUnlocker = nullptr;
     }
   }
   NS_IMETHOD Run()
   {
     if (PointerUnlocker::sActiveUnlocker == this) {
       PointerUnlocker::sActiveUnlocker = nullptr;
     }
     NS_ENSURE_STATE(nsFocusManager::GetFocusManager());
     nsPIDOMWindow* focused =
       nsFocusManager::GetFocusManager()->GetFocusedWindow();
     nsCOMPtr<nsIDocument> pointerLockedDoc =
       do_QueryReferent(EventStateManager::sPointerLockedDoc);
     if (pointerLockedDoc &&
         !nsContentUtils::IsInPointerLockContext(focused)) {
       nsIDocument::UnlockPointer();
     }
     return NS_OK;
   }
   static PointerUnlocker* sActiveUnlocker;
 };
 PointerUnlocker*
 PointerUnlocker::sActiveUnlocker = nullptr;
 void
 nsFocusManager::SetFocusedWindowInternal(nsPIDOMWindow* aWindow)
 {
   if (!PointerUnlocker::sActiveUnlocker &&
       nsContentUtils::IsInPointerLockContext(mFocusedWindow) &&
       !nsContentUtils::IsInPointerLockContext(aWindow)) {
     nsCOMPtr<nsIRunnable> runnable = new PointerUnlocker();
     NS_DispatchToCurrentThread(runnable);
   }
   mFocusedWindow = aWindow;
 }
 void
 nsFocusManager::MarkUncollectableForCCGeneration(uint32_t aGeneration)
 {
   if (!sInstance) {
     return;
   }
   if (sInstance->mActiveWindow) {
     sInstance->mActiveWindow->
       MarkUncollectableForCCGeneration(aGeneration);
   }
   if (sInstance->mFocusedWindow) {
     sInstance->mFocusedWindow->
       MarkUncollectableForCCGeneration(aGeneration);
   }
   if (sInstance->mWindowBeingLowered) {
     sInstance->mWindowBeingLowered->
       MarkUncollectableForCCGeneration(aGeneration);
   }
   if (sInstance->mFocusedContent) {
     sInstance->mFocusedContent->OwnerDoc()->
       MarkUncollectableForCCGeneration(aGeneration);
   }
   if (sInstance->mFirstBlurEvent) {
     sInstance->mFirstBlurEvent->OwnerDoc()->
       MarkUncollectableForCCGeneration(aGeneration);
   }
   if (sInstance->mFirstFocusEvent) {
     sInstance->mFirstFocusEvent->OwnerDoc()->
       MarkUncollectableForCCGeneration(aGeneration);
   }
   if (sInstance->mMouseDownEventHandlingDocument) {
     sInstance->mMouseDownEventHandlingDocument->
       MarkUncollectableForCCGeneration(aGeneration);
   }
 }
 nsresult
 NS_NewFocusManager(nsIFocusManager** aResult)
 {
   NS_IF_ADDREF(*aResult = nsFocusManager::GetFocusManager());
   return NS_OK;
 }

The Tor Browser / annotate

dom/base/nsFocusManager.cpp@6474c204b198 (annotated)

dom/base/nsFocusManager.cpp