The Tor Browser: layout/base/nsPresContext.cpp@6474c204b198 (annotated)

layout/base/nsPresContext.cpp@6474c204b198 (annotated)

layout/base/nsPresContext.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/. */
 /* a presentation of a document, part 1 */
 #include "mozilla/ArrayUtils.h"
 #include "mozilla/DebugOnly.h"
 #include "mozilla/EventDispatcher.h"
 #include "mozilla/EventStateManager.h"
 #include "base/basictypes.h"
 #include "nsCOMPtr.h"
 #include "nsPresContext.h"
 #include "nsIPresShell.h"
 #include "nsDocShell.h"
 #include "nsIContentViewer.h"
 #include "nsPIDOMWindow.h"
 #include "nsStyleSet.h"
 #include "nsIContent.h"
 #include "nsIFrame.h"
 #include "nsIDocument.h"
 #include "nsIPrintSettings.h"
 #include "nsILanguageAtomService.h"
 #include "mozilla/LookAndFeel.h"
 #include "nsIInterfaceRequestorUtils.h"
 #include "nsIWeakReferenceUtils.h"
 #include "nsAutoPtr.h"
 #include "nsThreadUtils.h"
 #include "nsFrameManager.h"
 #include "nsLayoutUtils.h"
 #include "nsViewManager.h"
 #include "RestyleManager.h"
 #include "nsCSSRuleProcessor.h"
 #include "nsRuleNode.h"
 #include "gfxPlatform.h"
 #include "nsCSSRules.h"
 #include "nsFontFaceLoader.h"
 #include "mozilla/EventListenerManager.h"
 #include "prenv.h"
 #include "nsObjectFrame.h"
 #include "nsTransitionManager.h"
 #include "nsAnimationManager.h"
 #include "mozilla/MemoryReporting.h"
 #include "mozilla/dom/Element.h"
 #include "nsIMessageManager.h"
 #include "mozilla/dom/MediaQueryList.h"
 #include "nsSMILAnimationController.h"
 #include "mozilla/css/ImageLoader.h"
 #include "mozilla/dom/TabChild.h"
 #include "nsRefreshDriver.h"
 #include "Layers.h"
 #include "nsIDOMEvent.h"
 #include "gfxPrefs.h"
 #include "nsString.h"
 #include "nsUnicharUtils.h"
 #include "nsContentUtils.h"
 #include "nsCxPusher.h"
 #include "nsPIWindowRoot.h"
 #include "mozilla/Preferences.h"
 // Needed for Start/Stop of Image Animation
 #include "imgIContainer.h"
 #include "nsIImageLoadingContent.h"
 #include "nsCSSParser.h"
 #include "nsBidiUtils.h"
 #include "nsServiceManagerUtils.h"
 #include "URL.h"
 using namespace mozilla;
 using namespace mozilla::dom;
 using namespace mozilla::layers;
 uint8_t gNotifySubDocInvalidationData;
 /**
  * Layer UserData for ContainerLayers that want to be notified
  * of local invalidations of them and their descendant layers.
  * Pass a callback to ComputeDifferences to have these called.
  */
 class ContainerLayerPresContext : public LayerUserData {
 public:
   nsPresContext* mPresContext;
 };
 namespace {
 class CharSetChangingRunnable : public nsRunnable
 {
 public:
   CharSetChangingRunnable(nsPresContext* aPresContext,
                           const nsCString& aCharSet)
     : mPresContext(aPresContext),
       mCharSet(aCharSet)
   {
   }
   NS_IMETHOD Run()
   {
     mPresContext->DoChangeCharSet(mCharSet);
     return NS_OK;
   }
 private:
   nsRefPtr<nsPresContext> mPresContext;
   nsCString mCharSet;
 };
 } // anonymous namespace
 nscolor
 nsPresContext::MakeColorPref(const nsString& aColor)
 {
   nsCSSParser parser;
   nsCSSValue value;
   if (!parser.ParseColorString(aColor, nullptr, 0, value)) {
     // Any better choices?
     return NS_RGB(0, 0, 0);
   }
   nscolor color;
   return nsRuleNode::ComputeColor(value, this, nullptr, color)
     ? color
     : NS_RGB(0, 0, 0);
 }
 bool
 nsPresContext::IsDOMPaintEventPending()
 {
   if (mFireAfterPaintEvents) {
     return true;
   }
   if (GetDisplayRootPresContext()->GetRootPresContext()->mRefreshDriver->ViewManagerFlushIsPending()) {
     // Since we're promising that there will be a MozAfterPaint event
     // fired, we record an empty invalidation in case display list
     // invalidation doesn't invalidate anything further.
     NotifyInvalidation(nsRect(0, 0, 0, 0), 0);
     NS_ASSERTION(mFireAfterPaintEvents, "Why aren't we planning to fire the event?");
     return true;
   }
   return false;
 }
 void
 nsPresContext::PrefChangedCallback(const char* aPrefName, void* instance_data)
 {
   nsRefPtr<nsPresContext>  presContext =
     static_cast<nsPresContext*>(instance_data);
   NS_ASSERTION(nullptr != presContext, "bad instance data");
   if (nullptr != presContext) {
     presContext->PreferenceChanged(aPrefName);
   }
 }
 void
 nsPresContext::PrefChangedUpdateTimerCallback(nsITimer *aTimer, void *aClosure)
 {
   nsPresContext*  presContext = (nsPresContext*)aClosure;
   NS_ASSERTION(presContext != nullptr, "bad instance data");
   if (presContext)
     presContext->UpdateAfterPreferencesChanged();
 }
 static bool
 IsVisualCharset(const nsCString& aCharset)
 {
   if (aCharset.LowerCaseEqualsLiteral("ibm862")             // Hebrew
       || aCharset.LowerCaseEqualsLiteral("iso-8859-8") ) {  // Hebrew
     return true; // visual text type
   }
   else {
     return false; // logical text type
   }
 }
   // NOTE! nsPresContext::operator new() zeroes out all members, so don't
   // bother initializing members to 0.
 nsPresContext::nsPresContext(nsIDocument* aDocument, nsPresContextType aType)
   : mType(aType), mDocument(aDocument), mBaseMinFontSize(0),
     mTextZoom(1.0), mFullZoom(1.0), mLastFontInflationScreenWidth(-1.0),
     mPageSize(-1, -1), mPPScale(1.0f),
     mViewportStyleOverflow(NS_STYLE_OVERFLOW_AUTO, NS_STYLE_OVERFLOW_AUTO),
     mImageAnimationModePref(imgIContainer::kNormalAnimMode),
     mAllInvalidated(false),
     mPaintFlashing(false), mPaintFlashingInitialized(false)
 {
   // NOTE! nsPresContext::operator new() zeroes out all members, so don't
   // bother initializing members to 0.
   mDoScaledTwips = true;
   SetBackgroundImageDraw(true);		// always draw the background
   SetBackgroundColorDraw(true);
   mBackgroundColor = NS_RGB(0xFF, 0xFF, 0xFF);
   mUseDocumentColors = true;
   mUseDocumentFonts = true;
   // the minimum font-size is unconstrained by default
   mLinkColor = NS_RGB(0x00, 0x00, 0xEE);
   mActiveLinkColor = NS_RGB(0xEE, 0x00, 0x00);
   mVisitedLinkColor = NS_RGB(0x55, 0x1A, 0x8B);
   mUnderlineLinks = true;
   mSendAfterPaintToContent = false;
   mFocusTextColor = mDefaultColor;
   mFocusBackgroundColor = mBackgroundColor;
   mFocusRingWidth = 1;
   mBodyTextColor = mDefaultColor;
   if (aType == eContext_Galley) {
     mMedium = nsGkAtoms::screen;
   } else {
     mMedium = nsGkAtoms::print;
     mPaginated = true;
   }
   mMediaEmulated = mMedium;
   if (!IsDynamic()) {
     mImageAnimationMode = imgIContainer::kDontAnimMode;
     mNeverAnimate = true;
   } else {
     mImageAnimationMode = imgIContainer::kNormalAnimMode;
     mNeverAnimate = false;
   }
   NS_ASSERTION(mDocument, "Null document");
   mUserFontSet = nullptr;
   mUserFontSetDirty = true;
   // if text perf logging enabled, init stats struct
   PRLogModuleInfo *log = gfxPlatform::GetLog(eGfxLog_textperf);
   if (log && log->level >= PR_LOG_WARNING) {
     mTextPerf = new gfxTextPerfMetrics();
   }
   PR_INIT_CLIST(&mDOMMediaQueryLists);
 }
 nsPresContext::~nsPresContext()
 {
   NS_PRECONDITION(!mShell, "Presshell forgot to clear our mShell pointer");
   SetShell(nullptr);
   NS_ABORT_IF_FALSE(PR_CLIST_IS_EMPTY(&mDOMMediaQueryLists),
                     "must not have media query lists left");
   // Disconnect the refresh driver *after* the transition manager, which
   // needs it.
   if (mRefreshDriver && mRefreshDriver->PresContext() == this) {
     mRefreshDriver->Disconnect();
   }
   if (mEventManager) {
     // unclear if these are needed, but can't hurt
     mEventManager->NotifyDestroyPresContext(this);
     mEventManager->SetPresContext(nullptr);
   }
   if (mPrefChangedTimer)
   {
     mPrefChangedTimer->Cancel();
     mPrefChangedTimer = nullptr;
   }
   // Unregister preference callbacks
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "font.",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "browser.display.",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "browser.underline_anchors",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "browser.anchor_color",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "browser.active_color",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "browser.visited_color",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "image.animation_mode",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "bidi.",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "dom.send_after_paint_to_content",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "gfx.font_rendering.",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "layout.css.dpi",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "layout.css.devPixelsPerPx",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "nglayout.debug.paint_flashing",
                                   this);
   Preferences::UnregisterCallback(nsPresContext::PrefChangedCallback,
                                   "nglayout.debug.paint_flashing_chrome",
                                   this);
 }
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsPresContext)
    NS_INTERFACE_MAP_ENTRY(nsISupports)
    NS_INTERFACE_MAP_ENTRY(nsIObserver)
 NS_INTERFACE_MAP_END
 NS_IMPL_CYCLE_COLLECTING_ADDREF(nsPresContext)
 NS_IMPL_CYCLE_COLLECTING_RELEASE_WITH_LAST_RELEASE(nsPresContext, LastRelease())
 void
 nsPresContext::LastRelease()
 {
   if (IsRoot()) {
     static_cast<nsRootPresContext*>(this)->CancelDidPaintTimer();
   }
 }
 NS_IMPL_CYCLE_COLLECTION_CLASS(nsPresContext)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsPresContext)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocument);
   // NS_IMPL_CYCLE_COLLECTION_TRAVERSE_RAWPTR(mDeviceContext); // not xpcom
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mEventManager);
   // NS_IMPL_CYCLE_COLLECTION_TRAVERSE_RAWPTR(mLanguage); // an atom
   // We own only the items in mDOMMediaQueryLists that have listeners;
   // this reference is managed by their AddListener and RemoveListener
   // methods.
   for (PRCList *l = PR_LIST_HEAD(&tmp->mDOMMediaQueryLists);
        l != &tmp->mDOMMediaQueryLists; l = PR_NEXT_LINK(l)) {
     MediaQueryList *mql = static_cast<MediaQueryList*>(l);
     if (mql->HasListeners()) {
       NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mDOMMediaQueryLists item");
       cb.NoteXPCOMChild(mql);
     }
   }
   // NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mTheme); // a service
   // NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mLangService); // a service
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPrintSettings);
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPrefChangedTimer);
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsPresContext)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocument);
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mDeviceContext); // worth bothering?
   if (tmp->mEventManager) {
     // unclear if these are needed, but can't hurt
     tmp->mEventManager->NotifyDestroyPresContext(tmp);
     tmp->mEventManager->SetPresContext(nullptr);
     tmp->mEventManager = nullptr;
   }
   // We own only the items in mDOMMediaQueryLists that have listeners;
   // this reference is managed by their AddListener and RemoveListener
   // methods.
   for (PRCList *l = PR_LIST_HEAD(&tmp->mDOMMediaQueryLists);
        l != &tmp->mDOMMediaQueryLists; ) {
     PRCList *next = PR_NEXT_LINK(l);
     MediaQueryList *mql = static_cast<MediaQueryList*>(l);
     mql->RemoveAllListeners();
     l = next;
   }
   // NS_RELEASE(tmp->mLanguage); // an atom
   // NS_IMPL_CYCLE_COLLECTION_UNLINK(mTheme); // a service
   // NS_IMPL_CYCLE_COLLECTION_UNLINK(mLangService); // a service
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mPrintSettings);
   if (tmp->mPrefChangedTimer)
   {
     tmp->mPrefChangedTimer->Cancel();
     tmp->mPrefChangedTimer = nullptr;
   }
 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
 #define MAKE_FONT_PREF_KEY(_pref, _s0, _s1) \
  _pref.Assign(_s0); \
  _pref.Append(_s1);
 static const char* const kGenericFont[] = {
   ".variable.",
   ".fixed.",
   ".serif.",
   ".sans-serif.",
   ".monospace.",
   ".cursive.",
   ".fantasy."
 };
 // whether no native theme service exists;
 // if this gets set to true, we'll stop asking for it.
 static bool sNoTheme = false;
 // Set to true when LookAndFeelChanged needs to be called.  This is used
 // because the look and feel is a service, so there's no need to notify it from
 // more than one prescontext.
 static bool sLookAndFeelChanged;
 // Set to true when ThemeChanged needs to be called on mTheme.  This is used
 // because mTheme is a service, so there's no need to notify it from more than
 // one prescontext.
 static bool sThemeChanged;
 const nsPresContext::LangGroupFontPrefs*
 nsPresContext::GetFontPrefsForLang(nsIAtom *aLanguage) const
 {
   // Get language group for aLanguage:
   nsresult rv = NS_OK;
   nsIAtom *langGroupAtom = nullptr;
   if (!aLanguage) {
     aLanguage = mLanguage;
   }
   if (aLanguage && mLangService) {
     langGroupAtom = mLangService->GetLanguageGroup(aLanguage, &rv);
   }
   if (NS_FAILED(rv) || !langGroupAtom) {
     langGroupAtom = nsGkAtoms::x_western; // Assume x-western is safe...
   }
   // Look for cached prefs for this lang group.
   // Most documents will only use one (or very few) language groups. Rather
   // than have the overhead of a hash lookup, we simply look along what will
   // typically be a very short (usually of length 1) linked list. There are 31
   // language groups, so in the worst case scenario we'll need to traverse 31
   // link items.
   LangGroupFontPrefs *prefs =
     const_cast<LangGroupFontPrefs*>(&mLangGroupFontPrefs);
   if (prefs->mLangGroup) { // if initialized
     DebugOnly<uint32_t> count = 0;
     for (;;) {
       NS_ASSERTION(++count < 35, "Lang group count exceeded!!!");
       if (prefs->mLangGroup == langGroupAtom) {
         return prefs;
       }
       if (!prefs->mNext) {
         break;
       }
       prefs = prefs->mNext;
     }
     // nothing cached, so go on and fetch the prefs for this lang group:
     prefs = prefs->mNext = new LangGroupFontPrefs;
   }
   prefs->mLangGroup = langGroupAtom;
   /* Fetch the font prefs to be used -- see bug 61883 for details.
      Not all prefs are needed upfront. Some are fallback prefs intended
      for the GFX font sub-system...
 ) unit : assumed to be the same for all language groups -------------
   font.size.unit = px | pt    XXX could be folded in the size... bug 90440
 ) attributes for generic fonts --------------------------------------
   font.default.[langGroup] = serif | sans-serif - fallback generic font
   font.name.[generic].[langGroup] = current user' selected font on the pref dialog
   font.name-list.[generic].[langGroup] = fontname1, fontname2, ... [factory pre-built list]
   font.size.[generic].[langGroup] = integer - settable by the user
   font.size-adjust.[generic].[langGroup] = "float" - settable by the user
   font.minimum-size.[langGroup] = integer - settable by the user
   */
   nsAutoCString langGroup;
   langGroupAtom->ToUTF8String(langGroup);
   prefs->mDefaultVariableFont.size = CSSPixelsToAppUnits(16);
   prefs->mDefaultFixedFont.size = CSSPixelsToAppUnits(13);
   nsAutoCString pref;
   // get the current applicable font-size unit
   enum {eUnit_unknown = -1, eUnit_px, eUnit_pt};
   int32_t unit = eUnit_px;
   nsAdoptingCString cvalue =
     Preferences::GetCString("font.size.unit");
   if (!cvalue.IsEmpty()) {
     if (cvalue.Equals("px")) {
       unit = eUnit_px;
     }
     else if (cvalue.Equals("pt")) {
       unit = eUnit_pt;
     }
     else {
       // XXX should really send this warning to the user (Error Console?).
       // And just default to unit = eUnit_px?
       NS_WARNING("unexpected font-size unit -- expected: 'px' or 'pt'");
       unit = eUnit_unknown;
     }
   }
   // get font.minimum-size.[langGroup]
   MAKE_FONT_PREF_KEY(pref, "font.minimum-size.", langGroup);
   int32_t size = Preferences::GetInt(pref.get());
   if (unit == eUnit_px) {
     prefs->mMinimumFontSize = CSSPixelsToAppUnits(size);
   }
   else if (unit == eUnit_pt) {
     prefs->mMinimumFontSize = CSSPointsToAppUnits(size);
   }
   nsFont* fontTypes[] = {
     &prefs->mDefaultVariableFont,
     &prefs->mDefaultFixedFont,
     &prefs->mDefaultSerifFont,
     &prefs->mDefaultSansSerifFont,
     &prefs->mDefaultMonospaceFont,
     &prefs->mDefaultCursiveFont,
     &prefs->mDefaultFantasyFont
   };
   static_assert(MOZ_ARRAY_LENGTH(fontTypes) == eDefaultFont_COUNT,
                 "FontTypes array count is not correct");
   // Get attributes specific to each generic font. We do not get the user's
   // generic-font-name-to-specific-family-name preferences because its the
   // generic name that should be fed into the cascade. It is up to the GFX
   // code to look up the font prefs to convert generic names to specific
   // family names as necessary.
   nsAutoCString generic_dot_langGroup;
   for (uint32_t eType = 0; eType < ArrayLength(fontTypes); ++eType) {
     generic_dot_langGroup.Assign(kGenericFont[eType]);
     generic_dot_langGroup.Append(langGroup);
     nsFont* font = fontTypes[eType];
     // set the default variable font (the other fonts are seen as 'generic' fonts
     // in GFX and will be queried there when hunting for alternative fonts)
     if (eType == eDefaultFont_Variable) {
       MAKE_FONT_PREF_KEY(pref, "font.name.variable.", langGroup);
       nsAdoptingString value = Preferences::GetString(pref.get());
       if (!value.IsEmpty()) {
         prefs->mDefaultVariableFont.name.Assign(value);
       }
       else {
         MAKE_FONT_PREF_KEY(pref, "font.default.", langGroup);
         value = Preferences::GetString(pref.get());
         if (!value.IsEmpty()) {
           prefs->mDefaultVariableFont.name.Assign(value);
         }
       }
     }
     else {
       if (eType == eDefaultFont_Monospace) {
         // This takes care of the confusion whereby people often expect "monospace"
         // to have the same default font-size as "-moz-fixed" (this tentative
         // size may be overwritten with the specific value for "monospace" when
         // "font.size.monospace.[langGroup]" is read -- see below)
         prefs->mDefaultMonospaceFont.size = prefs->mDefaultFixedFont.size;
       }
       else if (eType != eDefaultFont_Fixed) {
         // all the other generic fonts are initialized with the size of the
         // variable font, but their specific size can supersede later -- see below
         font->size = prefs->mDefaultVariableFont.size;
       }
     }
     // Bug 84398: for spec purists, a different font-size only applies to the
     // .variable. and .fixed. fonts and the other fonts should get |font-size-adjust|.
     // The problem is that only GfxWin has the support for |font-size-adjust|. So for
     // parity, we enable the ability to set a different font-size on all platforms.
     // get font.size.[generic].[langGroup]
     // size=0 means 'Auto', i.e., generic fonts retain the size of the variable font
     MAKE_FONT_PREF_KEY(pref, "font.size", generic_dot_langGroup);
     size = Preferences::GetInt(pref.get());
     if (size > 0) {
       if (unit == eUnit_px) {
         font->size = CSSPixelsToAppUnits(size);
       }
       else if (unit == eUnit_pt) {
         font->size = CSSPointsToAppUnits(size);
       }
     }
     // get font.size-adjust.[generic].[langGroup]
     // XXX only applicable on GFX ports that handle |font-size-adjust|
     MAKE_FONT_PREF_KEY(pref, "font.size-adjust", generic_dot_langGroup);
     cvalue = Preferences::GetCString(pref.get());
     if (!cvalue.IsEmpty()) {
       font->sizeAdjust = (float)atof(cvalue.get());
     }
 #ifdef DEBUG_rbs
     printf("%s Family-list:%s size:%d sizeAdjust:%.2f\n",
            generic_dot_langGroup.get(),
            NS_ConvertUTF16toUTF8(font->name).get(), font->size,
            font->sizeAdjust);
 #endif
   }
   return prefs;
 }
 void
 nsPresContext::GetDocumentColorPreferences()
 {
   // Make sure the preferences are initialized.  In the normal run,
   // they would already be, because gfxPlatform would have been created,
   // but in some reference tests, that is not the case.
   gfxPrefs::GetSingleton();
   int32_t useAccessibilityTheme = 0;
   bool usePrefColors = true;
   bool isChromeDocShell = false;
   nsIDocument* doc = mDocument->GetDisplayDocument();
   if (doc && doc->GetDocShell()) {
     isChromeDocShell = nsIDocShellTreeItem::typeChrome ==
                        doc->GetDocShell()->ItemType();
   } else {
     nsCOMPtr<nsIDocShellTreeItem> docShell(mContainer);
     if (docShell) {
       isChromeDocShell = nsIDocShellTreeItem::typeChrome == docShell->ItemType();
     }
   }
   mIsChromeOriginImage = mDocument->IsBeingUsedAsImage() &&
                          IsChromeURI(mDocument->GetDocumentURI());
   if (isChromeDocShell || mIsChromeOriginImage) {
     usePrefColors = false;
   } else {
     useAccessibilityTheme =
       LookAndFeel::GetInt(LookAndFeel::eIntID_UseAccessibilityTheme, 0);
     usePrefColors = !useAccessibilityTheme;
   }
   if (usePrefColors) {
     usePrefColors =
       !Preferences::GetBool("browser.display.use_system_colors", false);
   }
   if (usePrefColors) {
     nsAdoptingString colorStr =
       Preferences::GetString("browser.display.foreground_color");
     if (!colorStr.IsEmpty()) {
       mDefaultColor = MakeColorPref(colorStr);
     }
     colorStr = Preferences::GetString("browser.display.background_color");
     if (!colorStr.IsEmpty()) {
       mBackgroundColor = MakeColorPref(colorStr);
     }
   }
   else {
     mDefaultColor =
       LookAndFeel::GetColor(LookAndFeel::eColorID_WindowForeground,
                             NS_RGB(0x00, 0x00, 0x00));
     mBackgroundColor =
       LookAndFeel::GetColor(LookAndFeel::eColorID_WindowBackground,
                             NS_RGB(0xFF, 0xFF, 0xFF));
   }
   // Wherever we got the default background color from, ensure it is
   // opaque.
   mBackgroundColor = NS_ComposeColors(NS_RGB(0xFF, 0xFF, 0xFF),
                                       mBackgroundColor);
   mUseDocumentColors = !useAccessibilityTheme &&
     Preferences::GetBool("browser.display.use_document_colors",
                          mUseDocumentColors);
 }
 void
 nsPresContext::GetUserPreferences()
 {
   if (!GetPresShell()) {
     // No presshell means nothing to do here.  We'll do this when we
     // get a presshell.
     return;
   }
   mAutoQualityMinFontSizePixelsPref =
     Preferences::GetInt("browser.display.auto_quality_min_font_size");
   // * document colors
   GetDocumentColorPreferences();
   mSendAfterPaintToContent =
     Preferences::GetBool("dom.send_after_paint_to_content",
                          mSendAfterPaintToContent);
   // * link colors
   mUnderlineLinks =
     Preferences::GetBool("browser.underline_anchors", mUnderlineLinks);
   nsAdoptingString colorStr = Preferences::GetString("browser.anchor_color");
   if (!colorStr.IsEmpty()) {
     mLinkColor = MakeColorPref(colorStr);
   }
   colorStr = Preferences::GetString("browser.active_color");
   if (!colorStr.IsEmpty()) {
     mActiveLinkColor = MakeColorPref(colorStr);
   }
   colorStr = Preferences::GetString("browser.visited_color");
   if (!colorStr.IsEmpty()) {
     mVisitedLinkColor = MakeColorPref(colorStr);
   }
   mUseFocusColors =
     Preferences::GetBool("browser.display.use_focus_colors", mUseFocusColors);
   mFocusTextColor = mDefaultColor;
   mFocusBackgroundColor = mBackgroundColor;
   colorStr = Preferences::GetString("browser.display.focus_text_color");
   if (!colorStr.IsEmpty()) {
     mFocusTextColor = MakeColorPref(colorStr);
   }
   colorStr = Preferences::GetString("browser.display.focus_background_color");
   if (!colorStr.IsEmpty()) {
     mFocusBackgroundColor = MakeColorPref(colorStr);
   }
   mFocusRingWidth =
     Preferences::GetInt("browser.display.focus_ring_width", mFocusRingWidth);
   mFocusRingOnAnything =
     Preferences::GetBool("browser.display.focus_ring_on_anything",
                          mFocusRingOnAnything);
   mFocusRingStyle =
     Preferences::GetInt("browser.display.focus_ring_style", mFocusRingStyle);
   mBodyTextColor = mDefaultColor;
   // * use fonts?
   mUseDocumentFonts =
     Preferences::GetInt("browser.display.use_document_fonts") != 0;
   mMaxFonts =
     Preferences::GetInt("browser.display.max_font_count", -1);
   mMaxFontAttempts =
     Preferences::GetInt("browser.display.max_font_attempts", -1);
   mPrefScrollbarSide = Preferences::GetInt("layout.scrollbar.side");
   ResetCachedFontPrefs();
   // * image animation
   const nsAdoptingCString& animatePref =
     Preferences::GetCString("image.animation_mode");
   if (animatePref.Equals("normal"))
     mImageAnimationModePref = imgIContainer::kNormalAnimMode;
   else if (animatePref.Equals("none"))
     mImageAnimationModePref = imgIContainer::kDontAnimMode;
   else if (animatePref.Equals("once"))
     mImageAnimationModePref = imgIContainer::kLoopOnceAnimMode;
   else // dynamic change to invalid value should act like it does initially
     mImageAnimationModePref = imgIContainer::kNormalAnimMode;
   uint32_t bidiOptions = GetBidi();
   int32_t prefInt =
     Preferences::GetInt(IBMBIDI_TEXTDIRECTION_STR,
                         GET_BIDI_OPTION_DIRECTION(bidiOptions));
   SET_BIDI_OPTION_DIRECTION(bidiOptions, prefInt);
   mPrefBidiDirection = prefInt;
   prefInt =
     Preferences::GetInt(IBMBIDI_TEXTTYPE_STR,
                         GET_BIDI_OPTION_TEXTTYPE(bidiOptions));
   SET_BIDI_OPTION_TEXTTYPE(bidiOptions, prefInt);
   prefInt =
     Preferences::GetInt(IBMBIDI_NUMERAL_STR,
                         GET_BIDI_OPTION_NUMERAL(bidiOptions));
   SET_BIDI_OPTION_NUMERAL(bidiOptions, prefInt);
   prefInt =
     Preferences::GetInt(IBMBIDI_SUPPORTMODE_STR,
                         GET_BIDI_OPTION_SUPPORT(bidiOptions));
   SET_BIDI_OPTION_SUPPORT(bidiOptions, prefInt);
   // We don't need to force reflow: either we are initializing a new
   // prescontext or we are being called from UpdateAfterPreferencesChanged()
   // which triggers a reflow anyway.
   SetBidi(bidiOptions, false);
 }
 void
 nsPresContext::InvalidateThebesLayers()
 {
   if (!mShell)
     return;
   nsIFrame* rootFrame = mShell->FrameManager()->GetRootFrame();
   if (rootFrame) {
     // FrameLayerBuilder caches invalidation-related values that depend on the
     // appunits-per-dev-pixel ratio, so ensure that all ThebesLayer drawing
     // is completely flushed.
     rootFrame->InvalidateFrameSubtree();
   }
 }
 void
 nsPresContext::AppUnitsPerDevPixelChanged()
 {
   InvalidateThebesLayers();
   if (mDeviceContext) {
     mDeviceContext->FlushFontCache();
   }
   if (HasCachedStyleData()) {
     // All cached style data must be recomputed.
     MediaFeatureValuesChanged(eAlwaysRebuildStyle, NS_STYLE_HINT_REFLOW);
   }
   mCurAppUnitsPerDevPixel = AppUnitsPerDevPixel();
 }
 void
 nsPresContext::PreferenceChanged(const char* aPrefName)
 {
   nsDependentCString prefName(aPrefName);
   if (prefName.EqualsLiteral("layout.css.dpi") ||
       prefName.EqualsLiteral("layout.css.devPixelsPerPx")) {
     int32_t oldAppUnitsPerDevPixel = AppUnitsPerDevPixel();
     if (mDeviceContext->CheckDPIChange() && mShell) {
       nsCOMPtr<nsIPresShell> shell = mShell;
       // Re-fetch the view manager's window dimensions in case there's a deferred
       // resize which hasn't affected our mVisibleArea yet
       nscoord oldWidthAppUnits, oldHeightAppUnits;
       nsRefPtr<nsViewManager> vm = shell->GetViewManager();
       if (!vm) {
         return;
       }
       vm->GetWindowDimensions(&oldWidthAppUnits, &oldHeightAppUnits);
       float oldWidthDevPixels = oldWidthAppUnits/oldAppUnitsPerDevPixel;
       float oldHeightDevPixels = oldHeightAppUnits/oldAppUnitsPerDevPixel;
       nscoord width = NSToCoordRound(oldWidthDevPixels*AppUnitsPerDevPixel());
       nscoord height = NSToCoordRound(oldHeightDevPixels*AppUnitsPerDevPixel());
       vm->SetWindowDimensions(width, height);
       AppUnitsPerDevPixelChanged();
     }
     return;
   }
   if (StringBeginsWith(prefName, NS_LITERAL_CSTRING("font."))) {
     // Changes to font family preferences don't change anything in the
     // computed style data, so the style system won't generate a reflow
     // hint for us.  We need to do that manually.
     // FIXME We could probably also handle changes to
     // browser.display.auto_quality_min_font_size here, but that
     // probably also requires clearing the text run cache, so don't
     // bother (yet, anyway).
     mPrefChangePendingNeedsReflow = true;
   }
   if (StringBeginsWith(prefName, NS_LITERAL_CSTRING("bidi."))) {
     // Changes to bidi prefs need to trigger a reflow (see bug 443629)
     mPrefChangePendingNeedsReflow = true;
     // Changes to bidi.numeral also needs to empty the text run cache.
     // This is handled in gfxTextRunWordCache.cpp.
   }
   if (StringBeginsWith(prefName, NS_LITERAL_CSTRING("gfx.font_rendering."))) {
     // Changes to font_rendering prefs need to trigger a reflow
     mPrefChangePendingNeedsReflow = true;
   }
   // we use a zero-delay timer to coalesce multiple pref updates
   if (!mPrefChangedTimer)
   {
     mPrefChangedTimer = do_CreateInstance("@mozilla.org/timer;1");
     if (!mPrefChangedTimer)
       return;
     mPrefChangedTimer->InitWithFuncCallback(nsPresContext::PrefChangedUpdateTimerCallback, (void*)this, 0, nsITimer::TYPE_ONE_SHOT);
   }
   if (prefName.EqualsLiteral("nglayout.debug.paint_flashing") ||
       prefName.EqualsLiteral("nglayout.debug.paint_flashing_chrome")) {
     mPaintFlashingInitialized = false;
     return;
   }
 }
 void
 nsPresContext::UpdateAfterPreferencesChanged()
 {
   mPrefChangedTimer = nullptr;
   nsCOMPtr<nsIDocShellTreeItem> docShell(mContainer);
   if (docShell && nsIDocShellTreeItem::typeChrome == docShell->ItemType()) {
     return;
   }
   // Initialize our state from the user preferences
   GetUserPreferences();
   // update the presShell: tell it to set the preference style rules up
   if (mShell) {
     mShell->SetPreferenceStyleRules(true);
   }
   InvalidateThebesLayers();
   mDeviceContext->FlushFontCache();
   nsChangeHint hint = nsChangeHint(0);
   if (mPrefChangePendingNeedsReflow) {
     NS_UpdateHint(hint, NS_STYLE_HINT_REFLOW);
   }
   RebuildAllStyleData(hint);
 }
 nsresult
 nsPresContext::Init(nsDeviceContext* aDeviceContext)
 {
   NS_ASSERTION(!mInitialized, "attempt to reinit pres context");
   NS_ENSURE_ARG(aDeviceContext);
   mDeviceContext = aDeviceContext;
   if (mDeviceContext->SetPixelScale(mFullZoom))
     mDeviceContext->FlushFontCache();
   mCurAppUnitsPerDevPixel = AppUnitsPerDevPixel();
   mEventManager = new mozilla::EventStateManager();
   mTransitionManager = new nsTransitionManager(this);
   mAnimationManager = new nsAnimationManager(this);
   // FIXME: Why is mozilla:: needed?
   mRestyleManager = new mozilla::RestyleManager(this);
   if (mDocument->GetDisplayDocument()) {
     NS_ASSERTION(mDocument->GetDisplayDocument()->GetShell() &&
                  mDocument->GetDisplayDocument()->GetShell()->GetPresContext(),
                  "Why are we being initialized?");
     mRefreshDriver = mDocument->GetDisplayDocument()->GetShell()->
       GetPresContext()->RefreshDriver();
   } else {
     nsIDocument* parent = mDocument->GetParentDocument();
     // Unfortunately, sometimes |parent| here has no presshell because
     // printing screws up things.  Assert that in other cases it does,
     // but whenever the shell is null just fall back on using our own
     // refresh driver.
     NS_ASSERTION(!parent || mDocument->IsStaticDocument() || parent->GetShell(),
                  "How did we end up with a presshell if our parent doesn't "
                  "have one?");
     if (parent && parent->GetShell()) {
       NS_ASSERTION(parent->GetShell()->GetPresContext(),
                    "How did we get a presshell?");
       // We don't have our container set yet at this point
       nsCOMPtr<nsIDocShellTreeItem> ourItem = mDocument->GetDocShell();
       if (ourItem) {
         nsCOMPtr<nsIDocShellTreeItem> parentItem;
         ourItem->GetSameTypeParent(getter_AddRefs(parentItem));
         if (parentItem) {
           Element* containingElement =
             parent->FindContentForSubDocument(mDocument);
           if (!containingElement->IsXUL() ||
               !containingElement->
                 HasAttr(kNameSpaceID_None,
                         nsGkAtoms::forceOwnRefreshDriver)) {
             mRefreshDriver = parent->GetShell()->GetPresContext()->RefreshDriver();
           }
         }
       }
     }
     if (!mRefreshDriver) {
       mRefreshDriver = new nsRefreshDriver(this);
     }
   }
   // Initialise refresh tick counters for OMTA
   mLastStyleUpdateForAllAnimations =
     mLastUpdateThrottledAnimationStyle =
     mLastUpdateThrottledTransitionStyle = mRefreshDriver->MostRecentRefresh();
   mLangService = do_GetService(NS_LANGUAGEATOMSERVICE_CONTRACTID);
   // Register callbacks so we're notified when the preferences change
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "font.",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "browser.display.",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "browser.underline_anchors",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "browser.anchor_color",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "browser.active_color",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "browser.visited_color",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "image.animation_mode",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "bidi.",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "dom.send_after_paint_to_content",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "gfx.font_rendering.",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "layout.css.dpi",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "layout.css.devPixelsPerPx",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "nglayout.debug.paint_flashing",
                                 this);
   Preferences::RegisterCallback(nsPresContext::PrefChangedCallback,
                                 "nglayout.debug.paint_flashing_chrome",
                                 this);
   nsresult rv = mEventManager->Init();
   NS_ENSURE_SUCCESS(rv, rv);
   mEventManager->SetPresContext(this);
 #ifdef DEBUG
   mInitialized = true;
 #endif
   mBorderWidthTable[NS_STYLE_BORDER_WIDTH_THIN] = CSSPixelsToAppUnits(1);
   mBorderWidthTable[NS_STYLE_BORDER_WIDTH_MEDIUM] = CSSPixelsToAppUnits(3);
   mBorderWidthTable[NS_STYLE_BORDER_WIDTH_THICK] = CSSPixelsToAppUnits(5);
   return NS_OK;
 }
 // Note: We don't hold a reference on the shell; it has a reference to
 // us
 void
 nsPresContext::SetShell(nsIPresShell* aShell)
 {
   if (mUserFontSet) {
     // Clear out user font set if we have one
     mUserFontSet->Destroy();
     NS_RELEASE(mUserFontSet);
   }
   if (mShell) {
     // Remove ourselves as the charset observer from the shell's doc, because
     // this shell may be going away for good.
     nsIDocument *doc = mShell->GetDocument();
     if (doc) {
       doc->RemoveCharSetObserver(this);
     }
   }
   mShell = aShell;
   if (mShell) {
     nsIDocument *doc = mShell->GetDocument();
     NS_ASSERTION(doc, "expect document here");
     if (doc) {
       // Have to update PresContext's mDocument before calling any other methods.
       mDocument = doc;
     }
     // Initialize our state from the user preferences, now that we
     // have a presshell, and hence a document.
     GetUserPreferences();
     if (doc) {
       nsIURI *docURI = doc->GetDocumentURI();
       if (IsDynamic() && docURI) {
         bool isChrome = false;
         bool isRes = false;
         docURI->SchemeIs("chrome", &isChrome);
         docURI->SchemeIs("resource", &isRes);
         if (!isChrome && !isRes)
           mImageAnimationMode = mImageAnimationModePref;
         else
           mImageAnimationMode = imgIContainer::kNormalAnimMode;
       }
       if (mLangService) {
         doc->AddCharSetObserver(this);
         UpdateCharSet(doc->GetDocumentCharacterSet());
       }
     }
   } else {
     if (mTransitionManager) {
       mTransitionManager->Disconnect();
       mTransitionManager = nullptr;
     }
     if (mAnimationManager) {
       mAnimationManager->Disconnect();
       mAnimationManager = nullptr;
     }
     if (mRestyleManager) {
       mRestyleManager->Disconnect();
       mRestyleManager = nullptr;
     }
     if (IsRoot()) {
       // Have to cancel our plugin geometry timer, because the
       // callback for that depends on a non-null presshell.
       static_cast<nsRootPresContext*>(this)->CancelApplyPluginGeometryTimer();
     }
   }
 }
 void
 nsPresContext::DoChangeCharSet(const nsCString& aCharSet)
 {
   UpdateCharSet(aCharSet);
   mDeviceContext->FlushFontCache();
   RebuildAllStyleData(NS_STYLE_HINT_REFLOW);
 }
 void
 nsPresContext::UpdateCharSet(const nsCString& aCharSet)
 {
   if (mLangService) {
     mLanguage = mLangService->LookupCharSet(aCharSet.get());
     // this will be a language group (or script) code rather than a true language code
     // bug 39570: moved from nsLanguageAtomService::LookupCharSet()
     if (mLanguage == nsGkAtoms::Unicode) {
       mLanguage = mLangService->GetLocaleLanguage();
     }
     ResetCachedFontPrefs();
   }
   switch (GET_BIDI_OPTION_TEXTTYPE(GetBidi())) {
     case IBMBIDI_TEXTTYPE_LOGICAL:
       SetVisualMode(false);
       break;
     case IBMBIDI_TEXTTYPE_VISUAL:
       SetVisualMode(true);
       break;
     case IBMBIDI_TEXTTYPE_CHARSET:
     default:
       SetVisualMode(IsVisualCharset(aCharSet));
   }
 }
 NS_IMETHODIMP
 nsPresContext::Observe(nsISupports* aSubject,
                         const char* aTopic,
                         const char16_t* aData)
 {
   if (!nsCRT::strcmp(aTopic, "charset")) {
     nsRefPtr<CharSetChangingRunnable> runnable =
       new CharSetChangingRunnable(this, NS_LossyConvertUTF16toASCII(aData));
     return NS_DispatchToCurrentThread(runnable);
   }
   NS_WARNING("unrecognized topic in nsPresContext::Observe");
   return NS_ERROR_FAILURE;
 }
 nsPresContext*
 nsPresContext::GetParentPresContext()
 {
   nsIPresShell* shell = GetPresShell();
   if (shell) {
     nsViewManager* viewManager = shell->GetViewManager();
     if (viewManager) {
       nsView* view = viewManager->GetRootView();
       if (view) {
         view = view->GetParent(); // anonymous inner view
         if (view) {
           view = view->GetParent(); // subdocumentframe's view
           if (view) {
             nsIFrame* f = view->GetFrame();
             if (f) {
               return f->PresContext();
             }
           }
         }
       }
     }
   }
   return nullptr;
 }
 nsPresContext*
 nsPresContext::GetToplevelContentDocumentPresContext()
 {
   if (IsChrome())
     return nullptr;
   nsPresContext* pc = this;
   for (;;) {
     nsPresContext* parent = pc->GetParentPresContext();
     if (!parent || parent->IsChrome())
       return pc;
     pc = parent;
   }
 }
 nsIWidget*
 nsPresContext::GetNearestWidget(nsPoint* aOffset)
 {
   NS_ENSURE_TRUE(mShell, nullptr);
   nsIFrame* frame = mShell->GetRootFrame();
   NS_ENSURE_TRUE(frame, nullptr);
   return frame->GetView()->GetNearestWidget(aOffset);
 }
 nsIWidget*
 nsPresContext::GetRootWidget()
 {
   NS_ENSURE_TRUE(mShell, nullptr);
   nsViewManager* vm = mShell->GetViewManager();
   if (!vm) {
     return nullptr;
   }
   nsCOMPtr<nsIWidget> widget;
   vm->GetRootWidget(getter_AddRefs(widget));
   return widget.get();
 }
 // We may want to replace this with something faster, maybe caching the root prescontext
 nsRootPresContext*
 nsPresContext::GetRootPresContext()
 {
   nsPresContext* pc = this;
   for (;;) {
     nsPresContext* parent = pc->GetParentPresContext();
     if (!parent)
       break;
     pc = parent;
   }
   return pc->IsRoot() ? static_cast<nsRootPresContext*>(pc) : nullptr;
 }
 nsRootPresContext*
 nsPresContext::GetDisplayRootPresContext()
 {
   nsPresContext* pc = this;
   for (;;) {
     nsPresContext* parent = pc->GetParentPresContext();
     if (!parent) {
       // Not sure if this is always strictly the parent, but it works for GetRootPresContext
       // where the current pres context has no frames.
       nsIDocument *doc = pc->Document();
       if (doc) {
         doc = doc->GetParentDocument();
         if (doc) {
           nsIPresShell* shell = doc->GetShell();
           if (shell) {
             parent = shell->GetPresContext();
           }
         }
       }
     }
     if (!parent || parent == pc)
       break;
     pc = parent;
   }
   return pc->IsRoot() ? static_cast<nsRootPresContext*>(pc) : nullptr;
 }
 void
 nsPresContext::CompatibilityModeChanged()
 {
   if (!mShell)
     return;
   // enable/disable the QuirkSheet
   mShell->StyleSet()->
     EnableQuirkStyleSheet(CompatibilityMode() == eCompatibility_NavQuirks);
 }
 // Helper function for setting Anim Mode on image
 static void SetImgAnimModeOnImgReq(imgIRequest* aImgReq, uint16_t aMode)
 {
   if (aImgReq) {
     nsCOMPtr<imgIContainer> imgCon;
     aImgReq->GetImage(getter_AddRefs(imgCon));
     if (imgCon) {
       imgCon->SetAnimationMode(aMode);
     }
   }
 }
 // IMPORTANT: Assumption is that all images for a Presentation
 // have the same Animation Mode (pavlov said this was OK)
 //
 // Walks content and set the animation mode
 // this is a way to turn on/off image animations
 void nsPresContext::SetImgAnimations(nsIContent *aParent, uint16_t aMode)
 {
   nsCOMPtr<nsIImageLoadingContent> imgContent(do_QueryInterface(aParent));
   if (imgContent) {
     nsCOMPtr<imgIRequest> imgReq;
     imgContent->GetRequest(nsIImageLoadingContent::CURRENT_REQUEST,
                            getter_AddRefs(imgReq));
     SetImgAnimModeOnImgReq(imgReq, aMode);
   }
   uint32_t count = aParent->GetChildCount();
   for (uint32_t i = 0; i < count; ++i) {
     SetImgAnimations(aParent->GetChildAt(i), aMode);
   }
 }
 void
 nsPresContext::SetSMILAnimations(nsIDocument *aDoc, uint16_t aNewMode,
                                  uint16_t aOldMode)
 {
   if (aDoc->HasAnimationController()) {
     nsSMILAnimationController* controller = aDoc->GetAnimationController();
     switch (aNewMode)
     {
       case imgIContainer::kNormalAnimMode:
       case imgIContainer::kLoopOnceAnimMode:
         if (aOldMode == imgIContainer::kDontAnimMode)
           controller->Resume(nsSMILTimeContainer::PAUSE_USERPREF);
         break;
       case imgIContainer::kDontAnimMode:
         if (aOldMode != imgIContainer::kDontAnimMode)
           controller->Pause(nsSMILTimeContainer::PAUSE_USERPREF);
         break;
     }
   }
 }
 void
 nsPresContext::SetImageAnimationModeInternal(uint16_t aMode)
 {
   NS_ASSERTION(aMode == imgIContainer::kNormalAnimMode ||
                aMode == imgIContainer::kDontAnimMode ||
                aMode == imgIContainer::kLoopOnceAnimMode, "Wrong Animation Mode is being set!");
   // Image animation mode cannot be changed when rendering to a printer.
   if (!IsDynamic())
     return;
   // Now walk the content tree and set the animation mode
   // on all the images.
   if (mShell != nullptr) {
     nsIDocument *doc = mShell->GetDocument();
     if (doc) {
       doc->StyleImageLoader()->SetAnimationMode(aMode);
       Element *rootElement = doc->GetRootElement();
       if (rootElement) {
         SetImgAnimations(rootElement, aMode);
       }
       SetSMILAnimations(doc, aMode, mImageAnimationMode);
     }
   }
   mImageAnimationMode = aMode;
 }
 void
 nsPresContext::SetImageAnimationModeExternal(uint16_t aMode)
 {
   SetImageAnimationModeInternal(aMode);
 }
 const nsFont*
 nsPresContext::GetDefaultFont(uint8_t aFontID, nsIAtom *aLanguage) const
 {
   const LangGroupFontPrefs *prefs = GetFontPrefsForLang(aLanguage);
   const nsFont *font;
   switch (aFontID) {
     // Special (our default variable width font and fixed width font)
     case kPresContext_DefaultVariableFont_ID:
       font = &prefs->mDefaultVariableFont;
       break;
     case kPresContext_DefaultFixedFont_ID:
       font = &prefs->mDefaultFixedFont;
       break;
     // CSS
     case kGenericFont_serif:
       font = &prefs->mDefaultSerifFont;
       break;
     case kGenericFont_sans_serif:
       font = &prefs->mDefaultSansSerifFont;
       break;
     case kGenericFont_monospace:
       font = &prefs->mDefaultMonospaceFont;
       break;
     case kGenericFont_cursive:
       font = &prefs->mDefaultCursiveFont;
       break;
     case kGenericFont_fantasy:
       font = &prefs->mDefaultFantasyFont;
       break;
     default:
       font = nullptr;
       NS_ERROR("invalid arg");
       break;
   }
   return font;
 }
 PRBool
 nsPresContext::FontUseCountReached(const nsFont &font) {
   if (mMaxFonts < 0) {
     return PR_FALSE;
   }
   for (PRUint32 i = 0; i < mFontsUsed.Length(); i++) {
     if (mFontsUsed[i].name.Equals(font.name,
                                   nsCaseInsensitiveStringComparator())
         // XXX: Style is sometimes filled with garbage??
         /*&& mFontsUsed[i].style == font.style*/) {
       // seen it before: OK
       return PR_FALSE;
     }
   }
   if (mFontsUsed.Length() >= (unsigned)mMaxFonts) {
     return PR_TRUE;
   }
   return PR_FALSE;
 }
 PRBool
 nsPresContext::FontAttemptCountReached(const nsFont &font) {
   if (mMaxFontAttempts < 0) {
     return PR_FALSE;
   }
   for (PRUint32 i = 0; i < mFontsTried.Length(); i++) {
     if (mFontsTried[i].name.Equals(font.name,
                                   nsCaseInsensitiveStringComparator())
         // XXX: Style is sometimes filled with garbage??
         /*&& mFontsTried[i].style == font.style*/) {
       // seen it before: OK
       return PR_FALSE;
     }
   }
   if (mFontsTried.Length() >= (unsigned)mMaxFontAttempts) {
     return PR_TRUE;
   }
   return PR_FALSE;
 }
 void
 nsPresContext::AddFontUse(const nsFont &font) {
   if (mMaxFonts < 0) {
     return;
   }
   for (PRUint32 i = 0; i < mFontsUsed.Length(); i++) {
     if (mFontsUsed[i].name.Equals(font.name,
                                   nsCaseInsensitiveStringComparator())
         // XXX: Style is sometimes filled with garbage??
         /*&& mFontsUsed[i].style == font.style*/) {
       // seen it before: OK
       return;
     }
   }
   if (mFontsUsed.Length() >= (unsigned)mMaxFonts) {
     return;
   }
   mFontsUsed.AppendElement(font);
   return;
 }
 void
 nsPresContext::AddFontAttempt(const nsFont &font) {
   if (mMaxFontAttempts < 0) {
     return;
   }
   for (PRUint32 i = 0; i < mFontsTried.Length(); i++) {
     if (mFontsTried[i].name.Equals(font.name,
                                   nsCaseInsensitiveStringComparator())
         // XXX: Style is sometimes filled with garbage??
         /*&& mFontsTried[i].style == font.style*/) {
       // seen it before: OK
       return;
     }
   }
   if (mFontsTried.Length() >= (unsigned)mMaxFontAttempts) {
     return;
   }
   mFontsTried.AppendElement(font);
   return;
 }
 void
 nsPresContext::SetFullZoom(float aZoom)
 {
   if (!mShell || mFullZoom == aZoom) {
     return;
   }
   // Re-fetch the view manager's window dimensions in case there's a deferred
   // resize which hasn't affected our mVisibleArea yet
   nscoord oldWidthAppUnits, oldHeightAppUnits;
   mShell->GetViewManager()->GetWindowDimensions(&oldWidthAppUnits, &oldHeightAppUnits);
   float oldWidthDevPixels = oldWidthAppUnits / float(mCurAppUnitsPerDevPixel);
   float oldHeightDevPixels = oldHeightAppUnits / float(mCurAppUnitsPerDevPixel);
   mDeviceContext->SetPixelScale(aZoom);
   NS_ASSERTION(!mSupressResizeReflow, "two zooms happening at the same time? impossible!");
   mSupressResizeReflow = true;
   mFullZoom = aZoom;
   mShell->GetViewManager()->
     SetWindowDimensions(NSToCoordRound(oldWidthDevPixels * AppUnitsPerDevPixel()),
                         NSToCoordRound(oldHeightDevPixels * AppUnitsPerDevPixel()));
   AppUnitsPerDevPixelChanged();
   mSupressResizeReflow = false;
 }
 float
 nsPresContext::ScreenWidthInchesForFontInflation(bool* aChanged)
 {
   if (aChanged) {
     *aChanged = false;
   }
   nsDeviceContext *dx = DeviceContext();
   nsRect clientRect;
   dx->GetClientRect(clientRect); // FIXME: GetClientRect looks expensive
   float deviceWidthInches =
     float(clientRect.width) / float(dx->AppUnitsPerPhysicalInch());
   if (mLastFontInflationScreenWidth == -1.0) {
     mLastFontInflationScreenWidth = deviceWidthInches;
   }
   if (deviceWidthInches != mLastFontInflationScreenWidth && aChanged) {
     *aChanged = true;
     mLastFontInflationScreenWidth = deviceWidthInches;
   }
   return deviceWidthInches;
 }
 void
 nsPresContext::SetContainer(nsIDocShell* aDocShell)
 {
   if (aDocShell) {
     mContainer = static_cast<nsDocShell*>(aDocShell)->asWeakPtr();
   } else {
     mContainer = WeakPtr<nsDocShell>();
   }
   UpdateIsChrome();
   if (mContainer) {
     GetDocumentColorPreferences();
   }
 }
 nsISupports*
 nsPresContext::GetContainerWeakInternal() const
 {
   return static_cast<nsIDocShell*>(mContainer);
 }
 nsISupports*
 nsPresContext::GetContainerWeakExternal() const
 {
   return GetContainerWeakInternal();
 }
 nsIDocShell*
 nsPresContext::GetDocShell() const
 {
   return mContainer;
 }
 /* virtual */ void
 nsPresContext::Detach()
 {
   SetContainer(nullptr);
   SetLinkHandler(nullptr);
   if (mShell) {
     mShell->CancelInvalidatePresShellIfHidden();
   }
 }
 bool
 nsPresContext::ThrottledTransitionStyleIsUpToDate() const
 {
   return
     mLastUpdateThrottledTransitionStyle == mRefreshDriver->MostRecentRefresh();
 }
 void
 nsPresContext::TickLastUpdateThrottledTransitionStyle()
 {
   mLastUpdateThrottledTransitionStyle = mRefreshDriver->MostRecentRefresh();
 }
 bool
 nsPresContext::ThrottledAnimationStyleIsUpToDate() const
 {
   return
     mLastUpdateThrottledAnimationStyle == mRefreshDriver->MostRecentRefresh();
 }
 void
 nsPresContext::TickLastUpdateThrottledAnimationStyle()
 {
   mLastUpdateThrottledAnimationStyle = mRefreshDriver->MostRecentRefresh();
 }
 bool
 nsPresContext::StyleUpdateForAllAnimationsIsUpToDate()
 {
   return mLastStyleUpdateForAllAnimations == mRefreshDriver->MostRecentRefresh();
 }
 void
 nsPresContext::TickLastStyleUpdateForAllAnimations()
 {
   mLastStyleUpdateForAllAnimations = mRefreshDriver->MostRecentRefresh();
 }
 bool
 nsPresContext::BidiEnabledExternal() const
 {
   return BidiEnabledInternal();
 }
 bool
 nsPresContext::BidiEnabledInternal() const
 {
   return Document()->GetBidiEnabled();
 }
 void
 nsPresContext::SetBidiEnabled() const
 {
   if (mShell) {
     nsIDocument *doc = mShell->GetDocument();
     if (doc) {
       doc->SetBidiEnabled();
     }
   }
 }
 void
 nsPresContext::SetBidi(uint32_t aSource, bool aForceRestyle)
 {
   // Don't do all this stuff unless the options have changed.
   if (aSource == GetBidi()) {
     return;
   }
   NS_ASSERTION(!(aForceRestyle && (GetBidi() == 0)),
                "ForceReflow on new prescontext");
   Document()->SetBidiOptions(aSource);
   if (IBMBIDI_TEXTDIRECTION_RTL == GET_BIDI_OPTION_DIRECTION(aSource)
       || IBMBIDI_NUMERAL_HINDI == GET_BIDI_OPTION_NUMERAL(aSource)) {
     SetBidiEnabled();
   }
   if (IBMBIDI_TEXTTYPE_VISUAL == GET_BIDI_OPTION_TEXTTYPE(aSource)) {
     SetVisualMode(true);
   }
   else if (IBMBIDI_TEXTTYPE_LOGICAL == GET_BIDI_OPTION_TEXTTYPE(aSource)) {
     SetVisualMode(false);
   }
   else {
     nsIDocument* doc = mShell->GetDocument();
     if (doc) {
       SetVisualMode(IsVisualCharset(doc->GetDocumentCharacterSet()));
     }
   }
   if (aForceRestyle && mShell) {
     // Reconstruct the root document element's frame and its children,
     // because we need to trigger frame reconstruction for direction change.
     RebuildUserFontSet();
     mShell->ReconstructFrames();
   }
 }
 uint32_t
 nsPresContext::GetBidi() const
 {
   return Document()->GetBidiOptions();
 }
 bool
 nsPresContext::IsTopLevelWindowInactive()
 {
   nsCOMPtr<nsIDocShellTreeItem> treeItem(mContainer);
   if (!treeItem)
     return false;
   nsCOMPtr<nsIDocShellTreeItem> rootItem;
   treeItem->GetRootTreeItem(getter_AddRefs(rootItem));
   nsCOMPtr<nsPIDOMWindow> domWindow(do_GetInterface(rootItem));
   return domWindow && !domWindow->IsActive();
 }
 nsITheme*
 nsPresContext::GetTheme()
 {
   if (!sNoTheme && !mTheme) {
     mTheme = do_GetService("@mozilla.org/chrome/chrome-native-theme;1");
     if (!mTheme)
       sNoTheme = true;
   }
   return mTheme;
 }
 void
 nsPresContext::ThemeChanged()
 {
   if (!mPendingThemeChanged) {
     sLookAndFeelChanged = true;
     sThemeChanged = true;
     nsCOMPtr<nsIRunnable> ev =
       NS_NewRunnableMethod(this, &nsPresContext::ThemeChangedInternal);
     if (NS_SUCCEEDED(NS_DispatchToCurrentThread(ev))) {
       mPendingThemeChanged = true;
     }
   }
 }
 void
 nsPresContext::ThemeChangedInternal()
 {
   mPendingThemeChanged = false;
   // Tell the theme that it changed, so it can flush any handles to stale theme
   // data.
   if (mTheme && sThemeChanged) {
     mTheme->ThemeChanged();
     sThemeChanged = false;
   }
   // Clear all cached LookAndFeel colors.
   if (sLookAndFeelChanged) {
     LookAndFeel::Refresh();
     sLookAndFeelChanged = false;
   }
   // This will force the system metrics to be generated the next time they're used
   nsCSSRuleProcessor::FreeSystemMetrics();
   // Changes to system metrics can change media queries on them.
   // Changes in theme can change system colors (whose changes are
   // properly reflected in computed style data), system fonts (whose
   // changes are not), and -moz-appearance (whose changes likewise are
   // not), so we need to reflow.
   MediaFeatureValuesChanged(eAlwaysRebuildStyle, NS_STYLE_HINT_REFLOW);
 }
 void
 nsPresContext::SysColorChanged()
 {
   if (!mPendingSysColorChanged) {
     sLookAndFeelChanged = true;
     nsCOMPtr<nsIRunnable> ev =
       NS_NewRunnableMethod(this, &nsPresContext::SysColorChangedInternal);
     if (NS_SUCCEEDED(NS_DispatchToCurrentThread(ev))) {
       mPendingSysColorChanged = true;
     }
   }
 }
 void
 nsPresContext::SysColorChangedInternal()
 {
   mPendingSysColorChanged = false;
   if (sLookAndFeelChanged) {
      // Don't use the cached values for the system colors
     LookAndFeel::Refresh();
     sLookAndFeelChanged = false;
   }
   // Reset default background and foreground colors for the document since
   // they may be using system colors
   GetDocumentColorPreferences();
   // The system color values are computed to colors in the style data,
   // so normal style data comparison is sufficient here.
   RebuildAllStyleData(nsChangeHint(0));
 }
 void
 nsPresContext::UIResolutionChanged()
 {
   if (!mPendingUIResolutionChanged) {
     nsCOMPtr<nsIRunnable> ev =
       NS_NewRunnableMethod(this, &nsPresContext::UIResolutionChangedInternal);
     if (NS_SUCCEEDED(NS_DispatchToCurrentThread(ev))) {
       mPendingUIResolutionChanged = true;
     }
   }
 }
 /*static*/ bool
 nsPresContext::UIResolutionChangedSubdocumentCallback(nsIDocument* aDocument,
                                                       void* aData)
 {
   nsIPresShell* shell = aDocument->GetShell();
   if (shell) {
     nsPresContext* pc = shell->GetPresContext();
     if (pc) {
       pc->UIResolutionChangedInternal();
     }
   }
   return true;
 }
 void
 nsPresContext::UIResolutionChangedInternal()
 {
   mPendingUIResolutionChanged = false;
   mDeviceContext->CheckDPIChange();
   if (mCurAppUnitsPerDevPixel != AppUnitsPerDevPixel()) {
     AppUnitsPerDevPixelChanged();
   }
   mDocument->EnumerateSubDocuments(UIResolutionChangedSubdocumentCallback,
                                    nullptr);
 }
 void
 nsPresContext::EmulateMedium(const nsAString& aMediaType)
 {
   nsIAtom* previousMedium = Medium();
   mIsEmulatingMedia = true;
   nsAutoString mediaType;
   nsContentUtils::ASCIIToLower(aMediaType, mediaType);
   mMediaEmulated = do_GetAtom(mediaType);
   if (mMediaEmulated != previousMedium && mShell) {
     MediaFeatureValuesChanged(eRebuildStyleIfNeeded, nsChangeHint(0));
   }
 }
 void nsPresContext::StopEmulatingMedium()
 {
   nsIAtom* previousMedium = Medium();
   mIsEmulatingMedia = false;
   if (Medium() != previousMedium) {
     MediaFeatureValuesChanged(eRebuildStyleIfNeeded, nsChangeHint(0));
   }
 }
 void
 nsPresContext::RebuildAllStyleData(nsChangeHint aExtraHint)
 {
   if (!mShell) {
     // We must have been torn down. Nothing to do here.
     return;
   }
   mUsesRootEMUnits = false;
   mUsesViewportUnits = false;
   RebuildUserFontSet();
   RestyleManager()->RebuildAllStyleData(aExtraHint);
 }
 void
 nsPresContext::PostRebuildAllStyleDataEvent(nsChangeHint aExtraHint)
 {
   if (!mShell) {
     // We must have been torn down. Nothing to do here.
     return;
   }
   RestyleManager()->PostRebuildAllStyleDataEvent(aExtraHint);
 }
 void
 nsPresContext::MediaFeatureValuesChanged(StyleRebuildType aShouldRebuild,
                                          nsChangeHint aChangeHint)
 {
   NS_ASSERTION(aShouldRebuild == eAlwaysRebuildStyle || aChangeHint == 0,
                "If you don't know if we need a rebuild, how can you provide a hint?");
   mPendingMediaFeatureValuesChanged = false;
   // MediumFeaturesChanged updates the applied rules, so it always gets called.
   bool mediaFeaturesDidChange = mShell ? mShell->StyleSet()->MediumFeaturesChanged(this)
                                        : false;
   if (aShouldRebuild == eAlwaysRebuildStyle ||
       mediaFeaturesDidChange ||
       (mUsesViewportUnits && mPendingViewportChange)) {
     RebuildAllStyleData(aChangeHint);
   }
   mPendingViewportChange = false;
   if (!nsContentUtils::IsSafeToRunScript()) {
     NS_ABORT_IF_FALSE(mDocument->IsBeingUsedAsImage(),
                       "How did we get here?  Are we failing to notify "
                       "listeners that we should notify?");
     return;
   }
   // Media query list listeners should be notified from a queued task
   // (in HTML5 terms), although we also want to notify them on certain
   // flushes.  (We're already running off an event.)
   //
   // Note that we do this after the new style from media queries in
   // style sheets has been computed.
   if (!PR_CLIST_IS_EMPTY(&mDOMMediaQueryLists)) {
     // We build a list of all the notifications we're going to send
     // before we send any of them.  (The spec says the notifications
     // should be a queued task, so any removals that happen during the
     // notifications shouldn't affect what gets notified.)  Furthermore,
     // we hold strong pointers to everything we're going to make
     // notification calls to, since each notification involves calling
     // arbitrary script that might otherwise destroy these objects, or,
     // for that matter, |this|.
     //
     // Note that we intentionally send the notifications to media query
     // list in the order they were created and, for each list, to the
     // listeners in the order added.
     MediaQueryList::NotifyList notifyList;
     for (PRCList *l = PR_LIST_HEAD(&mDOMMediaQueryLists);
          l != &mDOMMediaQueryLists; l = PR_NEXT_LINK(l)) {
       MediaQueryList *mql = static_cast<MediaQueryList*>(l);
       mql->MediumFeaturesChanged(notifyList);
     }
     if (!notifyList.IsEmpty()) {
       nsPIDOMWindow *win = mDocument->GetInnerWindow();
       nsCOMPtr<EventTarget> et = do_QueryInterface(win);
       nsCxPusher pusher;
       for (uint32_t i = 0, i_end = notifyList.Length(); i != i_end; ++i) {
         if (pusher.RePush(et)) {
           nsAutoMicroTask mt;
           MediaQueryList::HandleChangeData &d = notifyList[i];
           ErrorResult result;
           d.callback->Call(*d.mql, result);
         }
       }
     }
     // NOTE:  When |notifyList| goes out of scope, our destructor could run.
   }
 }
 void
 nsPresContext::PostMediaFeatureValuesChangedEvent()
 {
   // FIXME: We should probably replace this event with use of
   // nsRefreshDriver::AddStyleFlushObserver (except the pres shell would
   // need to track whether it's been added).
   if (!mPendingMediaFeatureValuesChanged) {
     nsCOMPtr<nsIRunnable> ev =
       NS_NewRunnableMethod(this, &nsPresContext::HandleMediaFeatureValuesChangedEvent);
     if (NS_SUCCEEDED(NS_DispatchToCurrentThread(ev))) {
       mPendingMediaFeatureValuesChanged = true;
       mDocument->SetNeedStyleFlush();
     }
   }
 }
 void
 nsPresContext::HandleMediaFeatureValuesChangedEvent()
 {
   // Null-check mShell in case the shell has been destroyed (and the
   // event is the only thing holding the pres context alive).
   if (mPendingMediaFeatureValuesChanged && mShell) {
     MediaFeatureValuesChanged(eRebuildStyleIfNeeded);
   }
 }
 already_AddRefed<MediaQueryList>
 nsPresContext::MatchMedia(const nsAString& aMediaQueryList)
 {
   nsRefPtr<MediaQueryList> result = new MediaQueryList(this, aMediaQueryList);
   // Insert the new item at the end of the linked list.
   PR_INSERT_BEFORE(result, &mDOMMediaQueryLists);
   return result.forget();
 }
 nsCompatibility
 nsPresContext::CompatibilityMode() const
 {
   return Document()->GetCompatibilityMode();
 }
 void
 nsPresContext::SetPaginatedScrolling(bool aPaginated)
 {
   if (mType == eContext_PrintPreview || mType == eContext_PageLayout)
     mCanPaginatedScroll = aPaginated;
 }
 void
 nsPresContext::SetPrintSettings(nsIPrintSettings *aPrintSettings)
 {
   if (mMedium == nsGkAtoms::print)
     mPrintSettings = aPrintSettings;
 }
 bool
 nsPresContext::EnsureVisible()
 {
   nsCOMPtr<nsIDocShell> docShell(mContainer);
   if (docShell) {
     nsCOMPtr<nsIContentViewer> cv;
     docShell->GetContentViewer(getter_AddRefs(cv));
     // Make sure this is the content viewer we belong with
     if (cv) {
       nsRefPtr<nsPresContext> currentPresContext;
       cv->GetPresContext(getter_AddRefs(currentPresContext));
       if (currentPresContext == this) {
         // OK, this is us.  We want to call Show() on the content viewer.
         nsresult result = cv->Show();
         if (NS_SUCCEEDED(result)) {
           return true;
         }
       }
     }
   }
   return false;
 }
 #ifdef MOZ_REFLOW_PERF
 void
 nsPresContext::CountReflows(const char * aName, nsIFrame * aFrame)
 {
   if (mShell) {
     mShell->CountReflows(aName, aFrame);
   }
 }
 #endif
 void
 nsPresContext::UpdateIsChrome()
 {
   mIsChrome = mContainer &&
               nsIDocShellTreeItem::typeChrome == mContainer->ItemType();
 }
 /* virtual */ bool
 nsPresContext::HasAuthorSpecifiedRules(nsIFrame *aFrame, uint32_t ruleTypeMask) const
 {
   return
     nsRuleNode::HasAuthorSpecifiedRules(aFrame->StyleContext(),
                                         ruleTypeMask,
                                         UseDocumentColors());
 }
 gfxUserFontSet*
 nsPresContext::GetUserFontSetInternal()
 {
   // We want to initialize the user font set lazily the first time the
   // user asks for it, rather than building it too early and forcing
   // rule cascade creation.  Thus we try to enforce the invariant that
   // we *never* build the user font set until the first call to
   // GetUserFontSet.  However, once it's been requested, we can't wait
   // for somebody to call GetUserFontSet in order to rebuild it (see
   // comments below in RebuildUserFontSet for why).
 #ifdef DEBUG
   bool userFontSetGottenBefore = mGetUserFontSetCalled;
 #endif
   // Set mGetUserFontSetCalled up front, so that FlushUserFontSet will actually
   // flush.
   mGetUserFontSetCalled = true;
   if (mUserFontSetDirty) {
     // If this assertion fails, and there have actually been changes to
     // @font-face rules, then we will call StyleChangeReflow in
     // FlushUserFontSet.  If we're in the middle of reflow,
     // that's a bad thing to do, and the caller was responsible for
     // flushing first.  If we're not (e.g., in frame construction), it's
     // ok.
     NS_ASSERTION(!userFontSetGottenBefore || !mShell->IsReflowLocked(),
                  "FlushUserFontSet should have been called first");
     FlushUserFontSet();
   }
   return mUserFontSet;
 }
 gfxUserFontSet*
 nsPresContext::GetUserFontSetExternal()
 {
   return GetUserFontSetInternal();
 }
 void
 nsPresContext::FlushUserFontSet()
 {
   if (!mShell) {
     return; // we've been torn down
   }
   if (!mGetUserFontSetCalled) {
     return; // No one cares about this font set yet, but we want to be careful
             // to not unset our mUserFontSetDirty bit, so when someone really
             // does we'll create it.
   }
   if (mUserFontSetDirty) {
     if (gfxPlatform::GetPlatform()->DownloadableFontsEnabled()) {
       nsTArray<nsFontFaceRuleContainer> rules;
       if (!mShell->StyleSet()->AppendFontFaceRules(this, rules)) {
         if (mUserFontSet) {
           mUserFontSet->Destroy();
           NS_RELEASE(mUserFontSet);
         }
         return;
       }
       bool changed = false;
       if (rules.Length() == 0) {
         if (mUserFontSet) {
           mUserFontSet->Destroy();
           NS_RELEASE(mUserFontSet);
           changed = true;
         }
       } else {
         if (!mUserFontSet) {
           mUserFontSet = new nsUserFontSet(this);
           NS_ADDREF(mUserFontSet);
         }
         changed = mUserFontSet->UpdateRules(rules);
       }
       // We need to enqueue a style change reflow (for later) to
       // reflect that we're modifying @font-face rules.  (However,
       // without a reflow, nothing will happen to start any downloads
       // that are needed.)
       if (changed) {
         UserFontSetUpdated();
       }
     }
     mUserFontSetDirty = false;
   }
 }
 void
 nsPresContext::RebuildUserFontSet()
 {
   if (!mGetUserFontSetCalled) {
     // We want to lazily build the user font set the first time it's
     // requested (so we don't force creation of rule cascades too
     // early), so don't do anything now.
     return;
   }
   mUserFontSetDirty = true;
   mDocument->SetNeedStyleFlush();
   // Somebody has already asked for the user font set, so we need to
   // post an event to rebuild it.  Setting the user font set to be dirty
   // and lazily rebuilding it isn't sufficient, since it is only the act
   // of rebuilding it that will trigger the style change reflow that
   // calls GetUserFontSet.  (This reflow causes rebuilding of text runs,
   // which starts font loads, whose completion causes another style
   // change reflow).
   if (!mPostedFlushUserFontSet) {
     nsCOMPtr<nsIRunnable> ev =
       NS_NewRunnableMethod(this, &nsPresContext::HandleRebuildUserFontSet);
     if (NS_SUCCEEDED(NS_DispatchToCurrentThread(ev))) {
       mPostedFlushUserFontSet = true;
     }
   }
 }
 void
 nsPresContext::UserFontSetUpdated()
 {
   if (!mShell)
     return;
   // Changes to the set of available fonts can cause updates to layout by:
   //
   //   1. Changing the font used for text, which changes anything that
   //      depends on text measurement, including line breaking and
   //      intrinsic widths, and any other parts of layout that depend on
   //      font metrics.  This requires a style change reflow to update.
   //
   //   2. Changing the value of the 'ex' and 'ch' units in style data,
   //      which also depend on font metrics.  Updating this information
   //      requires rebuilding the rule tree from the top, avoiding the
   //      reuse of cached data even when no style rules have changed.
   PostRebuildAllStyleDataEvent(NS_STYLE_HINT_REFLOW);
 }
 void
 nsPresContext::EnsureSafeToHandOutCSSRules()
 {
   nsCSSStyleSheet::EnsureUniqueInnerResult res =
     mShell->StyleSet()->EnsureUniqueInnerOnCSSSheets();
   if (res == nsCSSStyleSheet::eUniqueInner_AlreadyUnique) {
     // Nothing to do.
     return;
   }
   MOZ_ASSERT(res == nsCSSStyleSheet::eUniqueInner_ClonedInner);
   RebuildAllStyleData(nsChangeHint(0));
 }
 void
 nsPresContext::FireDOMPaintEvent(nsInvalidateRequestList* aList)
 {
   nsPIDOMWindow* ourWindow = mDocument->GetWindow();
   if (!ourWindow)
     return;
   nsCOMPtr<EventTarget> dispatchTarget = do_QueryInterface(ourWindow);
   nsCOMPtr<EventTarget> eventTarget = dispatchTarget;
   if (!IsChrome() && !mSendAfterPaintToContent) {
     // Don't tell the window about this event, it should not know that
     // something happened in a subdocument. Tell only the chrome event handler.
     // (Events sent to the window get propagated to the chrome event handler
     // automatically.)
     dispatchTarget = do_QueryInterface(ourWindow->GetParentTarget());
     if (!dispatchTarget) {
       return;
     }
   }
   // Events sent to the window get propagated to the chrome event handler
   // automatically.
   nsCOMPtr<nsIDOMEvent> event;
   // This will empty our list in case dispatching the event causes more damage
   // (hopefully it won't, or we're likely to get an infinite loop! At least
   // it won't be blocking app execution though).
   NS_NewDOMNotifyPaintEvent(getter_AddRefs(event), eventTarget, this, nullptr,
                             NS_AFTERPAINT, aList);
   if (!event) {
     return;
   }
   // Even if we're not telling the window about the event (so eventTarget is
   // the chrome event handler, not the window), the window is still
   // logically the event target.
   event->SetTarget(eventTarget);
   event->SetTrusted(true);
   EventDispatcher::DispatchDOMEvent(dispatchTarget, nullptr, event, this,
                                     nullptr);
 }
 static bool
 MayHavePaintEventListenerSubdocumentCallback(nsIDocument* aDocument, void* aData)
 {
   bool *result = static_cast<bool*>(aData);
   nsIPresShell* shell = aDocument->GetShell();
   if (shell) {
     nsPresContext* pc = shell->GetPresContext();
     if (pc) {
       *result = pc->MayHavePaintEventListenerInSubDocument();
       // If we found a paint event listener, then we can stop enumerating
       // sub documents.
       return !*result;
     }
   }
   return true;
 }
 static bool
 MayHavePaintEventListener(nsPIDOMWindow* aInnerWindow)
 {
   if (!aInnerWindow)
     return false;
   if (aInnerWindow->HasPaintEventListeners())
     return true;
   EventTarget* parentTarget = aInnerWindow->GetParentTarget();
   if (!parentTarget)
     return false;
   EventListenerManager* manager = nullptr;
   if ((manager = parentTarget->GetExistingListenerManager()) &&
       manager->MayHavePaintEventListener()) {
     return true;
   }
   nsCOMPtr<nsINode> node;
   if (parentTarget != aInnerWindow->GetChromeEventHandler()) {
     nsCOMPtr<nsIInProcessContentFrameMessageManager> mm =
       do_QueryInterface(parentTarget);
     if (mm) {
       node = mm->GetOwnerContent();
     }
   }
   if (!node) {
     node = do_QueryInterface(parentTarget);
   }
   if (node)
     return MayHavePaintEventListener(node->OwnerDoc()->GetInnerWindow());
   nsCOMPtr<nsPIDOMWindow> window = do_QueryInterface(parentTarget);
   if (window)
     return MayHavePaintEventListener(window);
   nsCOMPtr<nsPIWindowRoot> root = do_QueryInterface(parentTarget);
   EventTarget* tabChildGlobal;
   return root &&
          (tabChildGlobal = root->GetParentTarget()) &&
          (manager = tabChildGlobal->GetExistingListenerManager()) &&
          manager->MayHavePaintEventListener();
 }
 bool
 nsPresContext::MayHavePaintEventListener()
 {
   return ::MayHavePaintEventListener(mDocument->GetInnerWindow());
 }
 bool
 nsPresContext::MayHavePaintEventListenerInSubDocument()
 {
   if (MayHavePaintEventListener()) {
     return true;
   }
   bool result = false;
   mDocument->EnumerateSubDocuments(MayHavePaintEventListenerSubdocumentCallback, &result);
   return result;
 }
 void
 nsPresContext::NotifyInvalidation(uint32_t aFlags)
 {
   nsIFrame* rootFrame = PresShell()->FrameManager()->GetRootFrame();
   NotifyInvalidation(rootFrame->GetVisualOverflowRect(), aFlags);
   mAllInvalidated = true;
 }
 void
 nsPresContext::NotifyInvalidation(const nsIntRect& aRect, uint32_t aFlags)
 {
   nsRect rect(DevPixelsToAppUnits(aRect.x),
               DevPixelsToAppUnits(aRect.y),
               DevPixelsToAppUnits(aRect.width),
               DevPixelsToAppUnits(aRect.height));
   NotifyInvalidation(rect, aFlags);
 }
 void
 nsPresContext::NotifyInvalidation(const nsRect& aRect, uint32_t aFlags)
 {
   MOZ_ASSERT(GetContainerWeak(), "Invalidation in detached pres context");
   // If there is no paint event listener, then we don't need to fire
   // the asynchronous event. We don't even need to record invalidation.
   // MayHavePaintEventListener is pretty cheap and we could make it
   // even cheaper by providing a more efficient
   // nsPIDOMWindow::GetListenerManager.
   if (mAllInvalidated) {
     return;
   }
   nsPresContext* pc;
   for (pc = this; pc; pc = pc->GetParentPresContext()) {
     if (pc->mFireAfterPaintEvents)
       break;
     pc->mFireAfterPaintEvents = true;
   }
   if (!pc) {
     nsRootPresContext* rpc = GetRootPresContext();
     if (rpc) {
       rpc->EnsureEventualDidPaintEvent();
     }
   }
   nsInvalidateRequestList::Request* request =
     mInvalidateRequestsSinceLastPaint.mRequests.AppendElement();
   if (!request)
     return;
   request->mRect = aRect;
   request->mFlags = aFlags;
 }
 /* static */ void
 nsPresContext::NotifySubDocInvalidation(ContainerLayer* aContainer,
                                         const nsIntRegion& aRegion)
 {
   ContainerLayerPresContext *data =
     static_cast<ContainerLayerPresContext*>(
       aContainer->GetUserData(&gNotifySubDocInvalidationData));
   if (!data) {
     return;
   }
   nsIntPoint topLeft = aContainer->GetVisibleRegion().GetBounds().TopLeft();
   nsIntRegionRectIterator iter(aRegion);
   while (const nsIntRect* r = iter.Next()) {
     nsIntRect rect = *r;
     //PresContext coordinate space is relative to the start of our visible
     // region. Is this really true? This feels like the wrong way to get the right
     // answer.
     rect.MoveBy(-topLeft);
     data->mPresContext->NotifyInvalidation(rect, 0);
   }
 }
 void
 nsPresContext::SetNotifySubDocInvalidationData(ContainerLayer* aContainer)
 {
   ContainerLayerPresContext* pres = new ContainerLayerPresContext;
   pres->mPresContext = this;
   aContainer->SetUserData(&gNotifySubDocInvalidationData, pres);
 }
 /* static */ void
 nsPresContext::ClearNotifySubDocInvalidationData(ContainerLayer* aContainer)
 {
   aContainer->SetUserData(&gNotifySubDocInvalidationData, nullptr);
 }
 struct NotifyDidPaintSubdocumentCallbackClosure {
   uint32_t mFlags;
   bool mNeedsAnotherDidPaintNotification;
 };
 static bool
 NotifyDidPaintSubdocumentCallback(nsIDocument* aDocument, void* aData)
 {
   NotifyDidPaintSubdocumentCallbackClosure* closure =
     static_cast<NotifyDidPaintSubdocumentCallbackClosure*>(aData);
   nsIPresShell* shell = aDocument->GetShell();
   if (shell) {
     nsPresContext* pc = shell->GetPresContext();
     if (pc) {
       pc->NotifyDidPaintForSubtree(closure->mFlags);
       if (pc->IsDOMPaintEventPending()) {
         closure->mNeedsAnotherDidPaintNotification = true;
       }
     }
   }
   return true;
 }
 class DelayedFireDOMPaintEvent : public nsRunnable {
 public:
   DelayedFireDOMPaintEvent(nsPresContext* aPresContext,
                            nsInvalidateRequestList* aList)
     : mPresContext(aPresContext)
   {
     MOZ_ASSERT(mPresContext->GetContainerWeak(),
                "DOMPaintEvent requested for a detached pres context");
     mList.TakeFrom(aList);
   }
   NS_IMETHOD Run() MOZ_OVERRIDE
   {
     // The pres context might have been detached during the delay -
     // that's fine, just don't fire the event.
     if (mPresContext->GetContainerWeak()) {
       mPresContext->FireDOMPaintEvent(&mList);
     }
     return NS_OK;
   }
   nsRefPtr<nsPresContext> mPresContext;
   nsInvalidateRequestList mList;
 };
 void
 nsPresContext::NotifyDidPaintForSubtree(uint32_t aFlags)
 {
   if (IsRoot()) {
     static_cast<nsRootPresContext*>(this)->CancelDidPaintTimer();
     if (!mFireAfterPaintEvents) {
       return;
     }
   }
   // Non-root prescontexts fire MozAfterPaint to all their descendants
   // unconditionally, even if no invalidations have been collected. This is
   // because we don't want to eat the cost of collecting invalidations for
   // every subdocument (which would require putting every subdocument in its
   // own layer).
   if (aFlags & nsIPresShell::PAINT_LAYERS) {
     mUndeliveredInvalidateRequestsBeforeLastPaint.TakeFrom(
         &mInvalidateRequestsSinceLastPaint);
     mAllInvalidated = false;
   }
   if (aFlags & nsIPresShell::PAINT_COMPOSITE) {
     nsCOMPtr<nsIRunnable> ev =
       new DelayedFireDOMPaintEvent(this, &mUndeliveredInvalidateRequestsBeforeLastPaint);
     nsContentUtils::AddScriptRunner(ev);
   }
   NotifyDidPaintSubdocumentCallbackClosure closure = { aFlags, false };
   mDocument->EnumerateSubDocuments(NotifyDidPaintSubdocumentCallback, &closure);
   if (!closure.mNeedsAnotherDidPaintNotification &&
       mInvalidateRequestsSinceLastPaint.IsEmpty() &&
       mUndeliveredInvalidateRequestsBeforeLastPaint.IsEmpty()) {
     // Nothing more to do for the moment.
     mFireAfterPaintEvents = false;
   } else {
     if (IsRoot()) {
       static_cast<nsRootPresContext*>(this)->EnsureEventualDidPaintEvent();
     }
   }
 }
 bool
 nsPresContext::HasCachedStyleData()
 {
   return mShell && mShell->StyleSet()->HasCachedStyleData();
 }
 static bool sGotInterruptEnv = false;
 enum InterruptMode {
   ModeRandom,
   ModeCounter,
   ModeEvent
 };
 // Controlled by the GECKO_REFLOW_INTERRUPT_MODE env var; allowed values are
 // "random" (except on Windows) or "counter".  If neither is used, the mode is
 // ModeEvent.
 static InterruptMode sInterruptMode = ModeEvent;
 #ifndef XP_WIN
 // Used for the "random" mode.  Controlled by the GECKO_REFLOW_INTERRUPT_SEED
 // env var.
 static uint32_t sInterruptSeed = 1;
 #endif
 // Used for the "counter" mode.  This is the number of unskipped interrupt
 // checks that have to happen before we interrupt.  Controlled by the
 // GECKO_REFLOW_INTERRUPT_FREQUENCY env var.
 static uint32_t sInterruptMaxCounter = 10;
 // Used for the "counter" mode.  This counts up to sInterruptMaxCounter and is
 // then reset to 0.
 static uint32_t sInterruptCounter;
 // Number of interrupt checks to skip before really trying to interrupt.
 // Controlled by the GECKO_REFLOW_INTERRUPT_CHECKS_TO_SKIP env var.
 static uint32_t sInterruptChecksToSkip = 200;
 // Number of milliseconds that a reflow should be allowed to run for before we
 // actually allow interruption.  Controlled by the
 // GECKO_REFLOW_MIN_NOINTERRUPT_DURATION env var.  Can't be initialized here,
 // because TimeDuration/TimeStamp is not safe to use in static constructors..
 static TimeDuration sInterruptTimeout;
 static void GetInterruptEnv()
 {
   char *ev = PR_GetEnv("GECKO_REFLOW_INTERRUPT_MODE");
   if (ev) {
 #ifndef XP_WIN
     if (PL_strcasecmp(ev, "random") == 0) {
       ev = PR_GetEnv("GECKO_REFLOW_INTERRUPT_SEED");
       if (ev) {
         sInterruptSeed = atoi(ev);
       }
       srandom(sInterruptSeed);
       sInterruptMode = ModeRandom;
     } else
 #endif
       if (PL_strcasecmp(ev, "counter") == 0) {
       ev = PR_GetEnv("GECKO_REFLOW_INTERRUPT_FREQUENCY");
       if (ev) {
         sInterruptMaxCounter = atoi(ev);
       }
       sInterruptCounter = 0;
       sInterruptMode = ModeCounter;
     }
   }
   ev = PR_GetEnv("GECKO_REFLOW_INTERRUPT_CHECKS_TO_SKIP");
   if (ev) {
     sInterruptChecksToSkip = atoi(ev);
   }
   ev = PR_GetEnv("GECKO_REFLOW_MIN_NOINTERRUPT_DURATION");
   int duration_ms = ev ? atoi(ev) : 100;
   sInterruptTimeout = TimeDuration::FromMilliseconds(duration_ms);
 }
 bool
 nsPresContext::HavePendingInputEvent()
 {
   switch (sInterruptMode) {
 #ifndef XP_WIN
     case ModeRandom:
       return (random() & 1);
 #endif
     case ModeCounter:
       if (sInterruptCounter < sInterruptMaxCounter) {
         ++sInterruptCounter;
         return false;
       }
       sInterruptCounter = 0;
       return true;
     default:
     case ModeEvent: {
       nsIFrame* f = PresShell()->GetRootFrame();
       if (f) {
         nsIWidget* w = f->GetNearestWidget();
         if (w) {
           return w->HasPendingInputEvent();
         }
       }
       return false;
     }
   }
 }
 void
 nsPresContext::ReflowStarted(bool aInterruptible)
 {
 #ifdef NOISY_INTERRUPTIBLE_REFLOW
   if (!aInterruptible) {
     printf("STARTING NONINTERRUPTIBLE REFLOW\n");
   }
 #endif
   // We don't support interrupting in paginated contexts, since page
   // sequences only handle initial reflow
   mInterruptsEnabled = aInterruptible && !IsPaginated() &&
                        nsLayoutUtils::InterruptibleReflowEnabled();
   // Don't set mHasPendingInterrupt based on HavePendingInputEvent() here.  If
   // we ever change that, then we need to update the code in
   // PresShell::DoReflow to only add the just-reflown root to dirty roots if
   // it's actually dirty.  Otherwise we can end up adding a root that has no
   // interruptible descendants, just because we detected an interrupt at reflow
   // start.
   mHasPendingInterrupt = false;
   mInterruptChecksToSkip = sInterruptChecksToSkip;
   if (mInterruptsEnabled) {
     mReflowStartTime = TimeStamp::Now();
   }
 }
 bool
 nsPresContext::CheckForInterrupt(nsIFrame* aFrame)
 {
   if (mHasPendingInterrupt) {
     mShell->FrameNeedsToContinueReflow(aFrame);
     return true;
   }
   if (!sGotInterruptEnv) {
     sGotInterruptEnv = true;
     GetInterruptEnv();
   }
   if (!mInterruptsEnabled) {
     return false;
   }
   if (mInterruptChecksToSkip > 0) {
     --mInterruptChecksToSkip;
     return false;
   }
   mInterruptChecksToSkip = sInterruptChecksToSkip;
   // Don't interrupt if it's been less than sInterruptTimeout since we started
   // the reflow.
   mHasPendingInterrupt =
     TimeStamp::Now() - mReflowStartTime > sInterruptTimeout &&
     HavePendingInputEvent() &&
     !IsChrome();
   if (mHasPendingInterrupt) {
 #ifdef NOISY_INTERRUPTIBLE_REFLOW
     printf("*** DETECTED pending interrupt (time=%lld)\n", PR_Now());
 #endif /* NOISY_INTERRUPTIBLE_REFLOW */
     mShell->FrameNeedsToContinueReflow(aFrame);
   }
   return mHasPendingInterrupt;
 }
 nsIFrame*
 nsPresContext::GetPrimaryFrameFor(nsIContent* aContent)
 {
   NS_PRECONDITION(aContent, "Don't do that");
   if (GetPresShell() &&
       GetPresShell()->GetDocument() == aContent->GetCurrentDoc()) {
     return aContent->GetPrimaryFrame();
   }
   return nullptr;
 }
 size_t
 nsPresContext::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
 {
   return mPropertyTable.SizeOfExcludingThis(aMallocSizeOf);
          mLangGroupFontPrefs.SizeOfExcludingThis(aMallocSizeOf);
   // Measurement of other members may be added later if DMD finds it is
   // worthwhile.
 }
 bool
 nsPresContext::IsRootContentDocument()
 {
   // We are a root content document if: we are not a resource doc, we are
   // not chrome, and we either have no parent or our parent is chrome.
   if (mDocument->IsResourceDoc()) {
     return false;
   }
   if (IsChrome()) {
     return false;
   }
   // We may not have a root frame, so use views.
   nsView* view = PresShell()->GetViewManager()->GetRootView();
   if (!view) {
     return false;
   }
   view = view->GetParent(); // anonymous inner view
   if (!view) {
     return true;
   }
   view = view->GetParent(); // subdocumentframe's view
   if (!view) {
     return true;
   }
   nsIFrame* f = view->GetFrame();
   return (f && f->PresContext()->IsChrome());
 }
 bool
 nsPresContext::IsCrossProcessRootContentDocument()
 {
   if (!IsRootContentDocument()) {
     return false;
   }
   if (XRE_GetProcessType() == GeckoProcessType_Default) {
     return true;
   }
   TabChild* tabChild = TabChild::GetFrom(mShell);
   return (tabChild && tabChild->IsRootContentDocument());
 }
 bool nsPresContext::GetPaintFlashing() const
 {
   if (!mPaintFlashingInitialized) {
     bool pref = Preferences::GetBool("nglayout.debug.paint_flashing");
     if (!pref && IsChrome()) {
       pref = Preferences::GetBool("nglayout.debug.paint_flashing_chrome");
     }
     mPaintFlashing = pref;
     mPaintFlashingInitialized = true;
   }
   return mPaintFlashing;
 }
 int32_t
 nsPresContext::AppUnitsPerDevPixel() const
 {
   return mDeviceContext->AppUnitsPerDevPixel();
 }
 nscoord
 nsPresContext::GfxUnitsToAppUnits(gfxFloat aGfxUnits) const
 {
   return mDeviceContext->GfxUnitsToAppUnits(aGfxUnits);
 }
 gfxFloat
 nsPresContext::AppUnitsToGfxUnits(nscoord aAppUnits) const
 {
   return mDeviceContext->AppUnitsToGfxUnits(aAppUnits);
 }
 bool
 nsPresContext::IsDeviceSizePageSize()
 {
   bool isDeviceSizePageSize = false;
   nsCOMPtr<nsIDocShell> docShell(mContainer);
   if (docShell) {
     isDeviceSizePageSize = docShell->GetDeviceSizeIsPageSize();
   }
   return isDeviceSizePageSize;
 }
 nsRootPresContext::nsRootPresContext(nsIDocument* aDocument,
                                      nsPresContextType aType)
   : nsPresContext(aDocument, aType),
     mDOMGeneration(0)
 {
 }
 nsRootPresContext::~nsRootPresContext()
 {
   NS_ASSERTION(mRegisteredPlugins.Count() == 0,
                "All plugins should have been unregistered");
   CancelDidPaintTimer();
   CancelApplyPluginGeometryTimer();
 }
 /* virtual */ void
 nsRootPresContext::Detach()
 {
   CancelDidPaintTimer();
   // XXXmats maybe also CancelApplyPluginGeometryTimer(); ?
   nsPresContext::Detach();
 }
 void
 nsRootPresContext::RegisterPluginForGeometryUpdates(nsIContent* aPlugin)
 {
   mRegisteredPlugins.PutEntry(aPlugin);
 }
 void
 nsRootPresContext::UnregisterPluginForGeometryUpdates(nsIContent* aPlugin)
 {
   mRegisteredPlugins.RemoveEntry(aPlugin);
 }
 static PLDHashOperator
 SetPluginHidden(nsRefPtrHashKey<nsIContent>* aEntry, void* userArg)
 {
   nsIFrame* root = static_cast<nsIFrame*>(userArg);
   nsObjectFrame* f = static_cast<nsObjectFrame*>(aEntry->GetKey()->GetPrimaryFrame());
   if (!f) {
     NS_WARNING("Null frame in SetPluginHidden");
     return PL_DHASH_NEXT;
   }
   if (!nsLayoutUtils::IsAncestorFrameCrossDoc(root, f)) {
     // f is not managed by this frame so we should ignore it.
     return PL_DHASH_NEXT;
   }
   f->SetEmptyWidgetConfiguration();
   return PL_DHASH_NEXT;
 }
 void
 nsRootPresContext::ComputePluginGeometryUpdates(nsIFrame* aFrame,
                                                 nsDisplayListBuilder* aBuilder,
                                                 nsDisplayList* aList)
 {
   if (mRegisteredPlugins.Count() == 0) {
     return;
   }
   // Initially make the next state for each plugin descendant of aFrame be
   // "hidden". Plugins that are visible will have their next state set to
   // unhidden by nsDisplayPlugin::ComputeVisibility.
   mRegisteredPlugins.EnumerateEntries(SetPluginHidden, aFrame);
   nsIFrame* rootFrame = FrameManager()->GetRootFrame();
   if (rootFrame && aBuilder->ContainsPluginItem()) {
     aBuilder->SetForPluginGeometry();
     aBuilder->SetAccurateVisibleRegions();
     // Merging and flattening has already been done and we should not do it
     // again. nsDisplayScroll(Info)Layer doesn't support trying to flatten
     // again.
     aBuilder->SetAllowMergingAndFlattening(false);
     nsRegion region = rootFrame->GetVisualOverflowRectRelativeToSelf();
     // nsDisplayPlugin::ComputeVisibility will automatically set a non-hidden
     // widget configuration for the plugin, if it's visible.
     aList->ComputeVisibilityForRoot(aBuilder, &region);
   }
 #ifdef XP_MACOSX
   // We control painting of Mac plugins, so just apply geometry updates now.
   // This is not happening during a paint event.
   ApplyPluginGeometryUpdates();
 #else
   InitApplyPluginGeometryTimer();
 #endif
 }
 static void
 ApplyPluginGeometryUpdatesCallback(nsITimer *aTimer, void *aClosure)
 {
   static_cast<nsRootPresContext*>(aClosure)->ApplyPluginGeometryUpdates();
 }
 void
 nsRootPresContext::InitApplyPluginGeometryTimer()
 {
   if (mApplyPluginGeometryTimer) {
     return;
   }
   // We'll apply the plugin geometry updates during the next compositing paint in this
   // presContext (either from nsPresShell::WillPaintWindow or from
   // nsPresShell::DidPaintWindow, depending on the platform).  But paints might
   // get optimized away if the old plugin geometry covers the invalid region,
   // so set a backup timer to do this too.  We want to make sure this
   // won't fire before our normal paint notifications, if those would
   // update the geometry, so set it for double the refresh driver interval.
   mApplyPluginGeometryTimer = do_CreateInstance("@mozilla.org/timer;1");
   if (mApplyPluginGeometryTimer) {
     mApplyPluginGeometryTimer->
       InitWithFuncCallback(ApplyPluginGeometryUpdatesCallback, this,
                            nsRefreshDriver::DefaultInterval() * 2,
                            nsITimer::TYPE_ONE_SHOT);
   }
 }
 void
 nsRootPresContext::CancelApplyPluginGeometryTimer()
 {
   if (mApplyPluginGeometryTimer) {
     mApplyPluginGeometryTimer->Cancel();
     mApplyPluginGeometryTimer = nullptr;
   }
 }
 static bool
 HasOverlap(const nsIntPoint& aOffset1, const nsTArray<nsIntRect>& aClipRects1,
            const nsIntPoint& aOffset2, const nsTArray<nsIntRect>& aClipRects2)
 {
   nsIntPoint offsetDelta = aOffset1 - aOffset2;
   for (uint32_t i = 0; i < aClipRects1.Length(); ++i) {
     for (uint32_t j = 0; j < aClipRects2.Length(); ++j) {
       if ((aClipRects1[i] + offsetDelta).Intersects(aClipRects2[j]))
         return true;
     }
   }
   return false;
 }
 /**
  * Given a list of plugin windows to move to new locations, sort the list
  * so that for each window move, the window moves to a location that
  * does not intersect other windows. This minimizes flicker and repainting.
  * It's not always possible to do this perfectly, since in general
  * we might have cycles. But we do our best.
  * We need to take into account that windows are clipped to particular
  * regions and the clip regions change as the windows are moved.
  */
 static void
 SortConfigurations(nsTArray<nsIWidget::Configuration>* aConfigurations)
 {
   if (aConfigurations->Length() > 10) {
     // Give up, we don't want to get bogged down here
     return;
   }
   nsTArray<nsIWidget::Configuration> pluginsToMove;
   pluginsToMove.SwapElements(*aConfigurations);
   // Our algorithm is quite naive. At each step we try to identify
   // a window that can be moved to its new location that won't overlap
   // any other windows at the new location. If there is no such
   // window, we just move the last window in the list anyway.
   while (!pluginsToMove.IsEmpty()) {
     // Find a window whose destination does not overlap any other window
     uint32_t i;
     for (i = 0; i + 1 < pluginsToMove.Length(); ++i) {
       nsIWidget::Configuration* config = &pluginsToMove[i];
       bool foundOverlap = false;
       for (uint32_t j = 0; j < pluginsToMove.Length(); ++j) {
         if (i == j)
           continue;
         nsIntRect bounds;
         pluginsToMove[j].mChild->GetBounds(bounds);
         nsAutoTArray<nsIntRect,1> clipRects;
         pluginsToMove[j].mChild->GetWindowClipRegion(&clipRects);
         if (HasOverlap(bounds.TopLeft(), clipRects,
                        config->mBounds.TopLeft(),
                        config->mClipRegion)) {
           foundOverlap = true;
           break;
         }
       }
       if (!foundOverlap)
         break;
     }
     // Note that we always move the last plugin in pluginsToMove, if we
     // can't find any other plugin to move
     aConfigurations->AppendElement(pluginsToMove[i]);
     pluginsToMove.RemoveElementAt(i);
   }
 }
 static PLDHashOperator
 PluginDidSetGeometryEnumerator(nsRefPtrHashKey<nsIContent>* aEntry, void* userArg)
 {
   nsObjectFrame* f = static_cast<nsObjectFrame*>(aEntry->GetKey()->GetPrimaryFrame());
   if (!f) {
     NS_WARNING("Null frame in PluginDidSetGeometryEnumerator");
     return PL_DHASH_NEXT;
   }
   f->DidSetWidgetGeometry();
   return PL_DHASH_NEXT;
 }
 struct PluginGetGeometryUpdateClosure {
   nsTArray<nsIWidget::Configuration> mConfigurations;
 };
 static PLDHashOperator
 PluginGetGeometryUpdate(nsRefPtrHashKey<nsIContent>* aEntry, void* userArg)
 {
   PluginGetGeometryUpdateClosure* closure =
     static_cast<PluginGetGeometryUpdateClosure*>(userArg);
   nsObjectFrame* f = static_cast<nsObjectFrame*>(aEntry->GetKey()->GetPrimaryFrame());
   if (!f) {
     NS_WARNING("Null frame in GetPluginGeometryUpdate");
     return PL_DHASH_NEXT;
   }
   f->GetWidgetConfiguration(&closure->mConfigurations);
   return PL_DHASH_NEXT;
 }
 void
 nsRootPresContext::ApplyPluginGeometryUpdates()
 {
   CancelApplyPluginGeometryTimer();
   PluginGetGeometryUpdateClosure closure;
   mRegisteredPlugins.EnumerateEntries(PluginGetGeometryUpdate, &closure);
   // Walk mRegisteredPlugins and ask each plugin for its configuration
   if (!closure.mConfigurations.IsEmpty()) {
     nsIWidget* widget = closure.mConfigurations[0].mChild->GetParent();
     NS_ASSERTION(widget, "Plugins must have a parent window");
     SortConfigurations(&closure.mConfigurations);
     widget->ConfigureChildren(closure.mConfigurations);
   }
   mRegisteredPlugins.EnumerateEntries(PluginDidSetGeometryEnumerator, nullptr);
 }
 static void
 NotifyDidPaintForSubtreeCallback(nsITimer *aTimer, void *aClosure)
 {
   nsPresContext* presContext = (nsPresContext*)aClosure;
   nsAutoScriptBlocker blockScripts;
   // This is a fallback if we don't get paint events for some reason
   // so we'll just pretend both layer painting and compositing happened.
   presContext->NotifyDidPaintForSubtree(
       nsIPresShell::PAINT_LAYERS | nsIPresShell::PAINT_COMPOSITE);
 }
 void
 nsRootPresContext::EnsureEventualDidPaintEvent()
 {
   if (mNotifyDidPaintTimer)
     return;
   mNotifyDidPaintTimer = do_CreateInstance("@mozilla.org/timer;1");
   if (!mNotifyDidPaintTimer)
     return;
   mNotifyDidPaintTimer->InitWithFuncCallback(NotifyDidPaintForSubtreeCallback,
                                              (void*)this, 100, nsITimer::TYPE_ONE_SHOT);
 }
 void
 nsRootPresContext::AddWillPaintObserver(nsIRunnable* aRunnable)
 {
   if (!mWillPaintFallbackEvent.IsPending()) {
     mWillPaintFallbackEvent = new RunWillPaintObservers(this);
     NS_DispatchToMainThread(mWillPaintFallbackEvent.get());
   }
   mWillPaintObservers.AppendElement(aRunnable);
 }
 /**
  * Run all runnables that need to get called before the next paint.
  */
 void
 nsRootPresContext::FlushWillPaintObservers()
 {
   mWillPaintFallbackEvent = nullptr;
   nsTArray<nsCOMPtr<nsIRunnable> > observers;
   observers.SwapElements(mWillPaintObservers);
   for (uint32_t i = 0; i < observers.Length(); ++i) {
     observers[i]->Run();
   }
 }
 size_t
 nsRootPresContext::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
 {
   return nsPresContext::SizeOfExcludingThis(aMallocSizeOf);
   // Measurement of the following members may be added later if DMD finds it is
   // worthwhile:
   // - mNotifyDidPaintTimer
   // - mRegisteredPlugins
   // - mWillPaintObservers
   // - mWillPaintFallbackEvent
 }

The Tor Browser / annotate

layout/base/nsPresContext.cpp@6474c204b198 (annotated)

layout/base/nsPresContext.cpp