The Tor Browser: content/base/public/nsContentUtils.h@6474c204b198 (annotated)

content/base/public/nsContentUtils.h@6474c204b198 (annotated)

content/base/public/nsContentUtils.h

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 namespace class for static content utilities. */
 #ifndef nsContentUtils_h___
 #define nsContentUtils_h___
 #if defined(XP_WIN)
 #include <float.h>
 #endif
 #if defined(SOLARIS)
 #include <ieeefp.h>
 #endif
 #include "js/TypeDecls.h"
 #include "js/Value.h"
 #include "js/RootingAPI.h"
 #include "mozilla/EventForwards.h"
 #include "mozilla/GuardObjects.h"
 #include "mozilla/TimeStamp.h"
 #include "nsContentListDeclarations.h"
 #include "nsMathUtils.h"
 #include "nsTArrayForwardDeclare.h"
 #include "Units.h"
 #if defined(XP_WIN)
 // Undefine LoadImage to prevent naming conflict with Windows.
 #undef LoadImage
 #endif
 class imgICache;
 class imgIContainer;
 class imgINotificationObserver;
 class imgIRequest;
 class imgLoader;
 class imgRequestProxy;
 class nsAutoScriptBlockerSuppressNodeRemoved;
 class nsHtml5StringParser;
 class nsIChannel;
 class nsIConsoleService;
 class nsIContent;
 class nsIContentPolicy;
 class nsIContentSecurityPolicy;
 class nsIDocShell;
 class nsIDocument;
 class nsIDocumentLoaderFactory;
 class nsIDocumentObserver;
 class nsIDOMDocument;
 class nsIDOMDocumentFragment;
 class nsIDOMEvent;
 class nsIDOMHTMLFormElement;
 class nsIDOMHTMLInputElement;
 class nsIDOMKeyEvent;
 class nsIDOMNode;
 class nsIDOMScriptObjectFactory;
 class nsIDOMWindow;
 class nsIDragSession;
 class nsIEditor;
 class nsIFragmentContentSink;
 class nsIFrame;
 class nsIImageLoadingContent;
 class nsIInterfaceRequestor;
 class nsIIOService;
 class nsIJSRuntimeService;
 class nsILineBreaker;
 class nsNameSpaceManager;
 class nsINodeInfo;
 class nsIObserver;
 class nsIParser;
 class nsIParserService;
 class nsIPresShell;
 class nsIPrincipal;
 class nsIRunnable;
 class nsIScriptContext;
 class nsIScriptGlobalObject;
 class nsIScriptSecurityManager;
 class nsIStringBundle;
 class nsIStringBundleService;
 class nsISupportsHashKey;
 class nsIURI;
 class nsIWidget;
 class nsIWordBreaker;
 class nsIXPConnect;
 class nsNodeInfoManager;
 class nsPIDOMWindow;
 class nsPresContext;
 class nsScriptObjectTracer;
 class nsStringBuffer;
 class nsStringHashKey;
 class nsTextFragment;
 class nsViewportInfo;
 class nsWrapperCache;
 class nsAttrValue;
 struct JSPropertyDescriptor;
 struct JSRuntime;
 struct nsIntMargin;
 template<class E> class nsCOMArray;
 template<class K, class V> class nsDataHashtable;
 template<class K, class V> class nsRefPtrHashtable;
 template<class T> class nsReadingIterator;
 namespace mozilla {
 class ErrorResult;
 class EventListenerManager;
 namespace dom {
 class DocumentFragment;
 class Element;
 class EventTarget;
 class Selection;
 } // namespace dom
 namespace layers {
 class LayerManager;
 } // namespace layers
 // Called back from DeferredFinalize.  Should add 'thing' to the array of smart
 // pointers in 'pointers', creating the array if 'pointers' is null, and return
 // the array.
 typedef void* (*DeferredFinalizeAppendFunction)(void* pointers, void* thing);
 // Called to finalize a number of objects. Slice is the number of objects
 // to finalize, or if it's UINT32_MAX, all objects should be finalized.
 // Return value indicates whether it finalized all objects in the buffer.
 typedef bool (*DeferredFinalizeFunction)(uint32_t slice, void* data);
 } // namespace mozilla
 class nsIBidiKeyboard;
 extern const char kLoadAsData[];
 // Stolen from nsReadableUtils, but that's OK, since we can declare the same
 // name multiple times.
 const nsAFlatString& EmptyString();
 const nsAFlatCString& EmptyCString();
 enum EventNameType {
   EventNameType_None = 0x0000,
   EventNameType_HTML = 0x0001,
   EventNameType_XUL = 0x0002,
   EventNameType_SVGGraphic = 0x0004, // svg graphic elements
   EventNameType_SVGSVG = 0x0008, // the svg element
   EventNameType_SMIL = 0x0010, // smil elements
   EventNameType_HTMLBodyOrFramesetOnly = 0x0020,
   EventNameType_HTMLXUL = 0x0003,
   EventNameType_All = 0xFFFF
 };
 struct EventNameMapping
 {
   nsIAtom* mAtom;
   uint32_t mId;
   int32_t  mType;
   uint32_t mStructType;
 };
 struct nsShortcutCandidate {
   nsShortcutCandidate(uint32_t aCharCode, bool aIgnoreShift) :
     mCharCode(aCharCode), mIgnoreShift(aIgnoreShift)
   {
   }
   uint32_t mCharCode;
   bool     mIgnoreShift;
 };
 class nsContentUtils
 {
   friend class nsAutoScriptBlockerSuppressNodeRemoved;
   typedef mozilla::dom::Element Element;
   typedef mozilla::TimeDuration TimeDuration;
 public:
   static nsresult Init();
   /**
    * Get a JSContext from the document's scope object.
    */
   static JSContext* GetContextFromDocument(nsIDocument *aDocument);
   static bool     IsCallerChrome();
   static bool     ThreadsafeIsCallerChrome();
   static bool     IsCallerXBL();
   static bool     IsImageSrcSetDisabled();
   static bool LookupBindingMember(JSContext* aCx, nsIContent *aContent,
                                   JS::Handle<jsid> aId,
                                   JS::MutableHandle<JSPropertyDescriptor> aDesc);
   /**
    * Returns the parent node of aChild crossing document boundaries.
    */
   static nsINode* GetCrossDocParentNode(nsINode* aChild);
   /**
    * Do not ever pass null pointers to this method.  If one of your
    * nsIContents is null, you have to decide for yourself what
    * "IsDescendantOf" really means.
    *
    * @param  aPossibleDescendant node to test for being a descendant of
    *         aPossibleAncestor
    * @param  aPossibleAncestor node to test for being an ancestor of
    *         aPossibleDescendant
    * @return true if aPossibleDescendant is a descendant of
    *         aPossibleAncestor (or is aPossibleAncestor).  false
    *         otherwise.
    */
   static bool ContentIsDescendantOf(const nsINode* aPossibleDescendant,
                                       const nsINode* aPossibleAncestor);
   /**
    * Similar to ContentIsDescendantOf, except will treat an HTMLTemplateElement
    * or ShadowRoot as an ancestor of things in the corresponding DocumentFragment.
    * See the concept of "host-including inclusive ancestor" in the DOM
    * specification.
    */
   static bool ContentIsHostIncludingDescendantOf(
     const nsINode* aPossibleDescendant, const nsINode* aPossibleAncestor);
   /**
    * Similar to ContentIsDescendantOf except it crosses document boundaries.
    */
   static bool ContentIsCrossDocDescendantOf(nsINode* aPossibleDescendant,
                                               nsINode* aPossibleAncestor);
   /*
    * This method fills the |aArray| with all ancestor nodes of |aNode|
    * including |aNode| at the zero index.
    */
   static nsresult GetAncestors(nsINode* aNode,
                                nsTArray<nsINode*>& aArray);
   /*
    * This method fills |aAncestorNodes| with all ancestor nodes of |aNode|
    * including |aNode| (QI'd to nsIContent) at the zero index.
    * For each ancestor, there is a corresponding element in |aAncestorOffsets|
    * which is the IndexOf the child in relation to its parent.
    *
    * This method just sucks.
    */
   static nsresult GetAncestorsAndOffsets(nsIDOMNode* aNode,
                                          int32_t aOffset,
                                          nsTArray<nsIContent*>* aAncestorNodes,
                                          nsTArray<int32_t>* aAncestorOffsets);
   /*
    * The out parameter, |aCommonAncestor| will be the closest node, if any,
    * to both |aNode| and |aOther| which is also an ancestor of each.
    * Returns an error if the two nodes are disconnected and don't have
    * a common ancestor.
    */
   static nsresult GetCommonAncestor(nsIDOMNode *aNode,
                                     nsIDOMNode *aOther,
                                     nsIDOMNode** aCommonAncestor);
   /**
    * Returns the common ancestor, if any, for two nodes. Returns null if the
    * nodes are disconnected.
    */
   static nsINode* GetCommonAncestor(nsINode* aNode1,
                                     nsINode* aNode2);
   /**
    * Returns true if aNode1 is before aNode2 in the same connected
    * tree.
    */
   static bool PositionIsBefore(nsINode* aNode1, nsINode* aNode2);
   /**
    *  Utility routine to compare two "points", where a point is a
    *  node/offset pair
    *  Returns -1 if point1 < point2, 1, if point1 > point2,
    *  0 if error or if point1 == point2.
    *  NOTE! If the two nodes aren't in the same connected subtree,
    *  the result is 1, and the optional aDisconnected parameter
    *  is set to true.
    */
   static int32_t ComparePoints(nsINode* aParent1, int32_t aOffset1,
                                nsINode* aParent2, int32_t aOffset2,
                                bool* aDisconnected = nullptr);
   static int32_t ComparePoints(nsIDOMNode* aParent1, int32_t aOffset1,
                                nsIDOMNode* aParent2, int32_t aOffset2,
                                bool* aDisconnected = nullptr);
   /**
    * Brute-force search of the element subtree rooted at aContent for
    * an element with the given id.  aId must be nonempty, otherwise
    * this method may return nodes even if they have no id!
    */
   static Element* MatchElementId(nsIContent *aContent, const nsAString& aId);
   /**
    * Similar to above, but to be used if one already has an atom for the ID
    */
   static Element* MatchElementId(nsIContent *aContent, const nsIAtom* aId);
   /**
    * Reverses the document position flags passed in.
    *
    * @param   aDocumentPosition   The document position flags to be reversed.
    *
    * @return  The reversed document position flags.
    *
    * @see nsIDOMNode
    */
   static uint16_t ReverseDocumentPosition(uint16_t aDocumentPosition);
   static uint32_t CopyNewlineNormalizedUnicodeTo(const nsAString& aSource,
                                                  uint32_t aSrcOffset,
                                                  char16_t* aDest,
                                                  uint32_t aLength,
                                                  bool& aLastCharCR);
   static uint32_t CopyNewlineNormalizedUnicodeTo(nsReadingIterator<char16_t>& aSrcStart, const nsReadingIterator<char16_t>& aSrcEnd, nsAString& aDest);
   static const nsDependentSubstring TrimCharsInSet(const char* aSet,
                                                    const nsAString& aValue);
   template<bool IsWhitespace(char16_t)>
   static const nsDependentSubstring TrimWhitespace(const nsAString& aStr,
                                                    bool aTrimTrailing = true);
   /**
    * Returns true if aChar is of class Ps, Pi, Po, Pf, or Pe.
    */
   static bool IsFirstLetterPunctuation(uint32_t aChar);
   static bool IsFirstLetterPunctuationAt(const nsTextFragment* aFrag, uint32_t aOffset);
   /**
    * Returns true if aChar is of class Lu, Ll, Lt, Lm, Lo, Nd, Nl or No
    */
   static bool IsAlphanumeric(uint32_t aChar);
   static bool IsAlphanumericAt(const nsTextFragment* aFrag, uint32_t aOffset);
   /*
    * Is the character an HTML whitespace character?
    *
    * We define whitespace using the list in HTML5 and css3-selectors:
    * U+0009, U+000A, U+000C, U+000D, U+0020
    *
    * HTML 4.01 also lists U+200B (zero-width space).
    */
   static bool IsHTMLWhitespace(char16_t aChar);
   /*
    * Returns whether the character is an HTML whitespace (see IsHTMLWhitespace)
    * or a nbsp character (U+00A0).
    */
   static bool IsHTMLWhitespaceOrNBSP(char16_t aChar);
   /**
    * Is the HTML local name a block element?
    */
   static bool IsHTMLBlock(nsIAtom* aLocalName);
   /**
    * Is the HTML local name a void element?
    */
   static bool IsHTMLVoid(nsIAtom* aLocalName);
   /**
    * Parse a margin string of format 'top, right, bottom, left' into
    * an nsIntMargin.
    *
    * @param aString the string to parse
    * @param aResult the resulting integer
    * @return whether the value could be parsed
    */
   static bool ParseIntMarginValue(const nsAString& aString, nsIntMargin& aResult);
   /**
    * Parse the value of the <font size=""> attribute according to the HTML5
    * spec as of April 16, 2012.
    *
    * @param aValue the value to parse
    * @return 1 to 7, or 0 if the value couldn't be parsed
    */
   static int32_t ParseLegacyFontSize(const nsAString& aValue);
   static void Shutdown();
   /**
    * Checks whether two nodes come from the same origin.
    */
   static nsresult CheckSameOrigin(const nsINode* aTrustedNode,
                                   nsIDOMNode* aUnTrustedNode);
   static nsresult CheckSameOrigin(const nsINode* aTrustedNode,
                                   const nsINode* unTrustedNode);
   // Check if the (JS) caller can access aNode.
   static bool CanCallerAccess(nsIDOMNode *aNode);
   static bool CanCallerAccess(nsINode* aNode);
   // Check if the (JS) caller can access aWindow.
   // aWindow can be either outer or inner window.
   static bool CanCallerAccess(nsPIDOMWindow* aWindow);
   /**
    * Get the window through the JS context that's currently on the stack.
    * If there's no JS context currently on the stack, returns null.
    */
   static nsPIDOMWindow *GetWindowFromCaller();
   /**
    * The two GetDocumentFrom* functions below allow a caller to get at a
    * document that is relevant to the currently executing script.
    *
    * GetDocumentFromCaller gets its document by looking at the last called
    * function and finding the document that the function itself relates to.
    * For example, consider two windows A and B in the same origin. B has a
    * function which does something that ends up needing the current document.
    * If a script in window A were to call B's function, GetDocumentFromCaller
    * would find that function (in B) and return B's document.
    *
    * GetDocumentFromContext gets its document by looking at the currently
    * executing context's global object and returning its document. Thus,
    * given the example above, GetDocumentFromCaller would see that the
    * currently executing script was in window A, and return A's document.
    */
   /**
    * Get the document from the currently executing function. This will return
    * the document that the currently executing function is in/from.
    *
    * @return The document or null if no JS Context.
    */
   static nsIDocument* GetDocumentFromCaller();
   /**
    * Get the document through the JS context that's currently on the stack.
    * If there's no JS context currently on the stack it will return null.
    * This will return the document of the calling script.
    *
    * @return The document or null if no JS context
    */
   static nsIDocument* GetDocumentFromContext();
   // Check if a node is in the document prolog, i.e. before the document
   // element.
   static bool InProlog(nsINode *aNode);
   static nsIParserService* GetParserService();
   static nsNameSpaceManager* NameSpaceManager()
   {
     return sNameSpaceManager;
   }
   static nsIIOService* GetIOService()
   {
     return sIOService;
   }
   static nsIBidiKeyboard* GetBidiKeyboard();
   /**
    * Get the cache security manager service. Can return null if the layout
    * module has been shut down.
    */
   static nsIScriptSecurityManager* GetSecurityManager()
   {
     return sSecurityManager;
   }
   /**
    * Get the ContentSecurityPolicy for a JS context.
    **/
   static bool GetContentSecurityPolicy(JSContext* aCx,
                                        nsIContentSecurityPolicy** aCSP);
   // Returns the subject principal. Guaranteed to return non-null. May only
   // be called when nsContentUtils is initialized.
   static nsIPrincipal* GetSubjectPrincipal();
   // Returns the principal of the given JS object. This should never be null
   // for any object in the XPConnect runtime.
   //
   // In general, being interested in the principal of an object is enough to
   // guarantee that the return value is non-null.
   static nsIPrincipal* GetObjectPrincipal(JSObject* aObj);
   static nsresult GenerateStateKey(nsIContent* aContent,
                                    const nsIDocument* aDocument,
                                    nsACString& aKey);
   /**
    * Create a new nsIURI from aSpec, using aBaseURI as the base.  The
    * origin charset of the new nsIURI will be the document charset of
    * aDocument.
    */
   static nsresult NewURIWithDocumentCharset(nsIURI** aResult,
                                             const nsAString& aSpec,
                                             nsIDocument* aDocument,
                                             nsIURI* aBaseURI);
   /**
    * Convert aInput (in encoding aEncoding) to UTF16 in aOutput.
    *
    * @param aEncoding the Gecko-canonical name of the encoding or the empty
    *                  string (meaning UTF-8)
    */
   static nsresult ConvertStringFromEncoding(const nsACString& aEncoding,
                                             const nsACString& aInput,
                                             nsAString& aOutput);
   /**
    * Determine whether a buffer begins with a BOM for UTF-8, UTF-16LE,
    * UTF-16BE
    *
    * @param aBuffer the buffer to check
    * @param aLength the length of the buffer
    * @param aCharset empty if not found
    * @return boolean indicating whether a BOM was detected.
    */
   static bool CheckForBOM(const unsigned char* aBuffer, uint32_t aLength,
                           nsACString& aCharset);
   /**
    * Returns true if |aName| is a valid name to be registered via
    * document.registerElement.
    */
   static bool IsCustomElementName(nsIAtom* aName);
   static nsresult CheckQName(const nsAString& aQualifiedName,
                              bool aNamespaceAware = true,
                              const char16_t** aColon = nullptr);
   static nsresult SplitQName(const nsIContent* aNamespaceResolver,
                              const nsAFlatString& aQName,
                              int32_t *aNamespace, nsIAtom **aLocalName);
   static nsresult GetNodeInfoFromQName(const nsAString& aNamespaceURI,
                                        const nsAString& aQualifiedName,
                                        nsNodeInfoManager* aNodeInfoManager,
                                        uint16_t aNodeType,
                                        nsINodeInfo** aNodeInfo);
   static void SplitExpatName(const char16_t *aExpatName, nsIAtom **aPrefix,
                              nsIAtom **aTagName, int32_t *aNameSpaceID);
   // Get a permission-manager setting for the given principal and type.
   // If the pref doesn't exist or if it isn't ALLOW_ACTION, false is
   // returned, otherwise true is returned. Always returns true for the
   // system principal, and false for a null principal.
   static bool IsSitePermAllow(nsIPrincipal* aPrincipal, const char* aType);
   // Get a permission-manager setting for the given principal and type.
   // If the pref doesn't exist or if it isn't DENY_ACTION, false is
   // returned, otherwise true is returned. Always returns false for the
   // system principal, and true for a null principal.
   static bool IsSitePermDeny(nsIPrincipal* aPrincipal, const char* aType);
   // Get a permission-manager setting for the given principal and type.
   // If the pref doesn't exist or if it isn't ALLOW_ACTION, false is
   // returned, otherwise true is returned. Always returns true for the
   // system principal, and false for a null principal.
   // This version checks the permission for an exact host match on
   // the principal
   static bool IsExactSitePermAllow(nsIPrincipal* aPrincipal, const char* aType);
   // Get a permission-manager setting for the given principal and type.
   // If the pref doesn't exist or if it isn't DENY_ACTION, false is
   // returned, otherwise true is returned. Always returns false for the
   // system principal, and true for a null principal.
   // This version checks the permission for an exact host match on
   // the principal
   static bool IsExactSitePermDeny(nsIPrincipal* aPrincipal, const char* aType);
   // Returns true if aDoc1 and aDoc2 have equal NodePrincipal()s.
   static bool HaveEqualPrincipals(nsIDocument* aDoc1, nsIDocument* aDoc2);
   static nsILineBreaker* LineBreaker()
   {
     return sLineBreaker;
   }
   static nsIWordBreaker* WordBreaker()
   {
     return sWordBreaker;
   }
   /**
    * Regster aObserver as a shutdown observer. A strong reference is held
    * to aObserver until UnregisterShutdownObserver is called.
    */
   static void RegisterShutdownObserver(nsIObserver* aObserver);
   static void UnregisterShutdownObserver(nsIObserver* aObserver);
   /**
    * @return true if aContent has an attribute aName in namespace aNameSpaceID,
    * and the attribute value is non-empty.
    */
   static bool HasNonEmptyAttr(const nsIContent* aContent, int32_t aNameSpaceID,
                                 nsIAtom* aName);
   /**
    * Method that gets the primary presContext for the node.
    *
    * @param aContent The content node.
    * @return the presContext, or nullptr if the content is not in a document
    *         (if GetCurrentDoc returns nullptr)
    */
   static nsPresContext* GetContextForContent(const nsIContent* aContent);
   /**
    * Method to do security and content policy checks on the image URI
    *
    * @param aURI uri of the image to be loaded
    * @param aContext the context the image is loaded in (eg an element)
    * @param aLoadingDocument the document we belong to
    * @param aLoadingPrincipal the principal doing the load
    * @param aImageBlockingStatus the nsIContentPolicy blocking status for this
    *        image.  This will be set even if a security check fails for the
    *        image, to some reasonable REJECT_* value.  This out param will only
    *        be set if it's non-null.
    * @return true if the load can proceed, or false if it is blocked.
    *         Note that aImageBlockingStatus, if set will always be an ACCEPT
    *         status if true is returned and always be a REJECT_* status if
    *         false is returned.
    */
   static bool CanLoadImage(nsIURI* aURI,
                              nsISupports* aContext,
                              nsIDocument* aLoadingDocument,
                              nsIPrincipal* aLoadingPrincipal,
                              int16_t* aImageBlockingStatus = nullptr);
   /**
    * Method to start an image load.  This does not do any security checks.
    * This method will attempt to make aURI immutable; a caller that wants to
    * keep a mutable version around should pass in a clone.
    *
    * @param aURI uri of the image to be loaded
    * @param aLoadingDocument the document we belong to
    * @param aLoadingPrincipal the principal doing the load
    * @param aReferrer the referrer URI
    * @param aObserver the observer for the image load
    * @param aLoadFlags the load flags to use.  See nsIRequest
    * @return the imgIRequest for the image load
    */
   static nsresult LoadImage(nsIURI* aURI,
                             nsIDocument* aLoadingDocument,
                             nsIPrincipal* aLoadingPrincipal,
                             nsIURI* aReferrer,
                             imgINotificationObserver* aObserver,
                             int32_t aLoadFlags,
                             const nsAString& initiatorType,
                             imgRequestProxy** aRequest);
   /**
    * Obtain an image loader that respects the given document/channel's privacy status.
    * Null document/channel arguments return the public image loader.
    */
   static imgLoader* GetImgLoaderForDocument(nsIDocument* aDoc);
   static imgLoader* GetImgLoaderForChannel(nsIChannel* aChannel);
   /**
    * Returns whether the given URI is in the image cache.
    */
   static bool IsImageInCache(nsIURI* aURI, nsIDocument* aDocument);
   /**
    * Method to get an imgIContainer from an image loading content
    *
    * @param aContent The image loading content.  Must not be null.
    * @param aRequest The image request [out]
    * @return the imgIContainer corresponding to the first frame of the image
    */
   static already_AddRefed<imgIContainer> GetImageFromContent(nsIImageLoadingContent* aContent, imgIRequest **aRequest = nullptr);
   /**
    * Helper method to call imgIRequest::GetStaticRequest.
    */
   static already_AddRefed<imgRequestProxy> GetStaticRequest(imgRequestProxy* aRequest);
   /**
    * Method that decides whether a content node is draggable
    *
    * @param aContent The content node to test.
    * @return whether it's draggable
    */
   static bool ContentIsDraggable(nsIContent* aContent);
   /**
    * Method that decides whether a content node is a draggable image
    *
    * @param aContent The content node to test.
    * @return whether it's a draggable image
    */
   static bool IsDraggableImage(nsIContent* aContent);
   /**
    * Method that decides whether a content node is a draggable link
    *
    * @param aContent The content node to test.
    * @return whether it's a draggable link
    */
   static bool IsDraggableLink(const nsIContent* aContent);
   /**
    * Convenience method to create a new nodeinfo that differs only by name
    * from aNodeInfo.
    */
   static nsresult NameChanged(nsINodeInfo* aNodeInfo, nsIAtom* aName,
                               nsINodeInfo** aResult);
   /**
    * Returns the appropriate event argument names for the specified
    * namespace and event name.  Added because we need to switch between
    * SVG's "evt" and the rest of the world's "event", and because onerror
    * takes 3 args.
    */
   static void GetEventArgNames(int32_t aNameSpaceID, nsIAtom *aEventName,
                                uint32_t *aArgCount, const char*** aArgNames);
   /**
    * If aNode is not an element, return true exactly when aContent's binding
    * parent is null.
    *
    * If aNode is an element, return true exactly when aContent's binding parent
    * is the same as aNode's.
    *
    * This method is particularly useful for callers who are trying to ensure
    * that they are working with a non-anonymous descendant of a given node.  If
    * aContent is a descendant of aNode, a return value of false from this
    * method means that it's an anonymous descendant from aNode's point of view.
    *
    * Both arguments to this method must be non-null.
    */
   static bool IsInSameAnonymousTree(const nsINode* aNode, const nsIContent* aContent);
   /**
    * Return the nsIXPConnect service.
    */
   static nsIXPConnect *XPConnect()
   {
     return sXPConnect;
   }
   /**
    * Report simple error message to the browser console
    *   @param aErrorText the error message
    *   @param classification Name of the module reporting error
    */
   static void LogSimpleConsoleError(const nsAString& aErrorText,
                                     const char * classification);
   /**
    * Report a non-localized error message to the error console.
    *   @param aErrorText the error message
    *   @param aErrorFlags See nsIScriptError.
    *   @param aCategory Name of module reporting error.
    *   @param aDocument Reference to the document which triggered the message.
    *   @param [aURI=nullptr] (Optional) URI of resource containing error.
    *   @param [aSourceLine=EmptyString()] (Optional) The text of the line that
               contains the error (may be empty).
    *   @param [aLineNumber=0] (Optional) Line number within resource
               containing error.
    *   @param [aColumnNumber=0] (Optional) Column number within resource
               containing error.
               If aURI is null, then aDocument->GetDocumentURI() is used.
    */
   static nsresult ReportToConsoleNonLocalized(const nsAString& aErrorText,
                                               uint32_t aErrorFlags,
                                               const nsACString& aCategory,
                                               nsIDocument* aDocument,
                                               nsIURI* aURI = nullptr,
                                               const nsAFlatString& aSourceLine
                                                 = EmptyString(),
                                               uint32_t aLineNumber = 0,
                                               uint32_t aColumnNumber = 0);
   /**
    * Report a localized error message to the error console.
    *   @param aErrorFlags See nsIScriptError.
    *   @param aCategory Name of module reporting error.
    *   @param aDocument Reference to the document which triggered the message.
    *   @param aFile Properties file containing localized message.
    *   @param aMessageName Name of localized message.
    *   @param [aParams=nullptr] (Optional) Parameters to be substituted into
               localized message.
    *   @param [aParamsLength=0] (Optional) Length of aParams.
    *   @param [aURI=nullptr] (Optional) URI of resource containing error.
    *   @param [aSourceLine=EmptyString()] (Optional) The text of the line that
               contains the error (may be empty).
    *   @param [aLineNumber=0] (Optional) Line number within resource
               containing error.
    *   @param [aColumnNumber=0] (Optional) Column number within resource
               containing error.
               If aURI is null, then aDocument->GetDocumentURI() is used.
    */
   enum PropertiesFile {
     eCSS_PROPERTIES,
     eXBL_PROPERTIES,
     eXUL_PROPERTIES,
     eLAYOUT_PROPERTIES,
     eFORMS_PROPERTIES,
     ePRINTING_PROPERTIES,
     eDOM_PROPERTIES,
     eHTMLPARSER_PROPERTIES,
     eSVG_PROPERTIES,
     eBRAND_PROPERTIES,
     eCOMMON_DIALOG_PROPERTIES,
     eMATHML_PROPERTIES,
     eSECURITY_PROPERTIES,
     PropertiesFile_COUNT
   };
   static nsresult ReportToConsole(uint32_t aErrorFlags,
                                   const nsACString& aCategory,
                                   nsIDocument* aDocument,
                                   PropertiesFile aFile,
                                   const char *aMessageName,
                                   const char16_t **aParams = nullptr,
                                   uint32_t aParamsLength = 0,
                                   nsIURI* aURI = nullptr,
                                   const nsAFlatString& aSourceLine
                                     = EmptyString(),
                                   uint32_t aLineNumber = 0,
                                   uint32_t aColumnNumber = 0);
   static void LogMessageToConsole(const char* aMsg, ...);
   /**
    * Get the localized string named |aKey| in properties file |aFile|.
    */
   static nsresult GetLocalizedString(PropertiesFile aFile,
                                      const char* aKey,
                                      nsXPIDLString& aResult);
   /**
    * A helper function that parses a sandbox attribute (of an <iframe> or
    * a CSP directive) and converts it to the set of flags used internally.
    *
    * @param sandboxAttr   the sandbox attribute
    * @return              the set of flags (0 if sandboxAttr is null)
    */
   static uint32_t ParseSandboxAttributeToFlags(const nsAttrValue* sandboxAttr);
   /**
    * Fill (with the parameters given) the localized string named |aKey| in
    * properties file |aFile|.
    */
 private:
   static nsresult FormatLocalizedString(PropertiesFile aFile,
                                         const char* aKey,
                                         const char16_t** aParams,
                                         uint32_t aParamsLength,
                                         nsXPIDLString& aResult);
 public:
   template<uint32_t N>
   static nsresult FormatLocalizedString(PropertiesFile aFile,
                                         const char* aKey,
                                         const char16_t* (&aParams)[N],
                                         nsXPIDLString& aResult)
   {
     return FormatLocalizedString(aFile, aKey, aParams, N, aResult);
   }
   /**
    * Returns true if aDocument is a chrome document
    */
   static bool IsChromeDoc(nsIDocument *aDocument);
   /**
    * Returns true if aDocument is in a docshell whose parent is the same type
    */
   static bool IsChildOfSameType(nsIDocument* aDoc);
   /**
   '* Returns true if the content-type will be rendered as plain-text.
    */
   static bool IsPlainTextType(const nsACString& aContentType);
   /**
    * Get the script file name to use when compiling the script
    * referenced by aURI. In cases where there's no need for any extra
    * security wrapper automation the script file name that's returned
    * will be the spec in aURI, else it will be the spec in aDocument's
    * URI followed by aURI's spec, separated by " -> ". Returns true
    * if the script file name was modified, false if it's aURI's
    * spec.
    */
   static bool GetWrapperSafeScriptFilename(nsIDocument *aDocument,
                                              nsIURI *aURI,
                                              nsACString& aScriptURI);
   /**
    * Returns true if aDocument belongs to a chrome docshell for
    * display purposes.  Returns false for null documents or documents
    * which do not belong to a docshell.
    */
   static bool IsInChromeDocshell(nsIDocument *aDocument);
   /**
    * Return the content policy service
    */
   static nsIContentPolicy *GetContentPolicy();
   /**
    * Quick helper to determine whether there are any mutation listeners
    * of a given type that apply to this content or any of its ancestors.
    * The method has the side effect to call document's MayDispatchMutationEvent
    * using aTargetForSubtreeModified as the parameter.
    *
    * @param aNode  The node to search for listeners
    * @param aType  The type of listener (NS_EVENT_BITS_MUTATION_*)
    * @param aTargetForSubtreeModified The node which is the target of the
    *                                  possible DOMSubtreeModified event.
    *
    * @return true if there are mutation listeners of the specified type
    */
   static bool HasMutationListeners(nsINode* aNode,
                                      uint32_t aType,
                                      nsINode* aTargetForSubtreeModified);
   /**
    * Quick helper to determine whether there are any mutation listeners
    * of a given type that apply to any content in this document. It is valid
    * to pass null for aDocument here, in which case this function always
    * returns true.
    *
    * @param aDocument The document to search for listeners
    * @param aType     The type of listener (NS_EVENT_BITS_MUTATION_*)
    *
    * @return true if there are mutation listeners of the specified type
    */
   static bool HasMutationListeners(nsIDocument* aDocument,
                                      uint32_t aType);
   /**
    * Synchronously fire DOMNodeRemoved on aChild. Only fires the event if
    * there really are listeners by checking using the HasMutationListeners
    * function above. The function makes sure to hold the relevant objects alive
    * for the duration of the event firing. However there are no guarantees
    * that any of the objects are alive by the time the function returns.
    * If you depend on that you need to hold references yourself.
    *
    * @param aChild    The node to fire DOMNodeRemoved at.
    * @param aParent   The parent of aChild.
    * @param aOwnerDoc The ownerDocument of aChild.
    */
   static void MaybeFireNodeRemoved(nsINode* aChild, nsINode* aParent,
                                    nsIDocument* aOwnerDoc);
   /**
    * This method creates and dispatches a trusted event.
    * Works only with events which can be created by calling
    * nsIDOMDocument::CreateEvent() with parameter "Events".
    * @param aDoc           The document which will be used to create the event.
    * @param aTarget        The target of the event, should be QIable to
    *                       nsIDOMEventTarget.
    * @param aEventName     The name of the event.
    * @param aCanBubble     Whether the event can bubble.
    * @param aCancelable    Is the event cancelable.
    * @param aDefaultAction Set to true if default action should be taken,
    *                       see nsIDOMEventTarget::DispatchEvent.
    */
   static nsresult DispatchTrustedEvent(nsIDocument* aDoc,
                                        nsISupports* aTarget,
                                        const nsAString& aEventName,
                                        bool aCanBubble,
                                        bool aCancelable,
                                        bool *aDefaultAction = nullptr);
   /**
    * This method creates and dispatches a untrusted event.
    * Works only with events which can be created by calling
    * nsIDOMDocument::CreateEvent() with parameter "Events".
    * @param aDoc           The document which will be used to create the event.
    * @param aTarget        The target of the event, should be QIable to
    *                       nsIDOMEventTarget.
    * @param aEventName     The name of the event.
    * @param aCanBubble     Whether the event can bubble.
    * @param aCancelable    Is the event cancelable.
    * @param aDefaultAction Set to true if default action should be taken,
    *                       see nsIDOMEventTarget::DispatchEvent.
    */
   static nsresult DispatchUntrustedEvent(nsIDocument* aDoc,
                                          nsISupports* aTarget,
                                          const nsAString& aEventName,
                                          bool aCanBubble,
                                          bool aCancelable,
                                          bool *aDefaultAction = nullptr);
   /**
    * This method creates and dispatches a trusted event to the chrome
    * event handler.
    * Works only with events which can be created by calling
    * nsIDOMDocument::CreateEvent() with parameter "Events".
    * @param aDocument      The document which will be used to create the event,
    *                       and whose window's chrome handler will be used to
    *                       dispatch the event.
    * @param aTarget        The target of the event, used for event->SetTarget()
    * @param aEventName     The name of the event.
    * @param aCanBubble     Whether the event can bubble.
    * @param aCancelable    Is the event cancelable.
    * @param aDefaultAction Set to true if default action should be taken,
    *                       see nsIDOMEventTarget::DispatchEvent.
    */
   static nsresult DispatchChromeEvent(nsIDocument* aDoc,
                                       nsISupports* aTarget,
                                       const nsAString& aEventName,
                                       bool aCanBubble,
                                       bool aCancelable,
                                       bool *aDefaultAction = nullptr);
   /**
    * Determines if an event attribute name (such as onclick) is valid for
    * a given element type. Types are from the EventNameType enumeration
    * defined above.
    *
    * @param aName the event name to look up
    * @param aType the type of content
    */
   static bool IsEventAttributeName(nsIAtom* aName, int32_t aType);
   /**
    * Return the event id for the event with the given name. The name is the
    * event name with the 'on' prefix. Returns NS_USER_DEFINED_EVENT if the
    * event doesn't match a known event name.
    *
    * @param aName the event name to look up
    */
   static uint32_t GetEventId(nsIAtom* aName);
   /**
    * Return the category for the event with the given name. The name is the
    * event name *without* the 'on' prefix. Returns NS_EVENT if the event
    * is not known to be in any particular category.
    *
    * @param aName the event name to look up
    */
   static uint32_t GetEventCategory(const nsAString& aName);
   /**
    * Return the event id and atom for the event with the given name.
    * The name is the event name *without* the 'on' prefix.
    * Returns NS_USER_DEFINED_EVENT on the aEventID if the
    * event doesn't match a known event name in the category.
    *
    * @param aName the event name to look up
    * @param aEventStruct only return event id in aEventStruct category
    */
   static nsIAtom* GetEventIdAndAtom(const nsAString& aName,
                                     uint32_t aEventStruct,
                                     uint32_t* aEventID);
   /**
    * Used only during traversal of the XPCOM graph by the cycle
    * collector: push a pointer to the listener manager onto the
    * children deque, if it exists. Do nothing if there is no listener
    * manager.
    *
    * Crucially: does not perform any refcounting operations.
    *
    * @param aNode The node to traverse.
    * @param children The buffer to push a listener manager pointer into.
    */
   static void TraverseListenerManager(nsINode *aNode,
                                       nsCycleCollectionTraversalCallback &cb);
   /**
    * Get the eventlistener manager for aNode, creating it if it does not
    * already exist.
    *
    * @param aNode The node for which to get the eventlistener manager.
    */
   static mozilla::EventListenerManager*
     GetListenerManagerForNode(nsINode* aNode);
   /**
    * Get the eventlistener manager for aNode, returning null if it does not
    * already exist.
    *
    * @param aNode The node for which to get the eventlistener manager.
    */
   static mozilla::EventListenerManager*
     GetExistingListenerManagerForNode(const nsINode* aNode);
   static void UnmarkGrayJSListenersInCCGenerationDocuments(uint32_t aGeneration);
   /**
    * Remove the eventlistener manager for aNode.
    *
    * @param aNode The node for which to remove the eventlistener manager.
    */
   static void RemoveListenerManager(nsINode *aNode);
   static bool IsInitialized()
   {
     return sInitialized;
   }
   /**
    * Checks if the localname/prefix/namespace triple is valid wrt prefix
    * and namespace according to the Namespaces in XML and DOM Code
    * specfications.
    *
    * @param aLocalname localname of the node
    * @param aPrefix prefix of the node
    * @param aNamespaceID namespace of the node
    */
   static bool IsValidNodeName(nsIAtom *aLocalName, nsIAtom *aPrefix,
                                 int32_t aNamespaceID);
   /**
    * Creates a DocumentFragment from text using a context node to resolve
    * namespaces.
    *
    * Note! In the HTML case with the HTML5 parser enabled, this is only called
    * from Range.createContextualFragment() and the implementation here is
    * quirky accordingly (html context node behaves like a body context node).
    * If you don't want that quirky behavior, don't use this method as-is!
    *
    * @param aContextNode the node which is used to resolve namespaces
    * @param aFragment the string which is parsed to a DocumentFragment
    * @param aReturn the resulting fragment
    * @param aPreventScriptExecution whether to mark scripts as already started
    */
   static nsresult CreateContextualFragment(nsINode* aContextNode,
                                            const nsAString& aFragment,
                                            bool aPreventScriptExecution,
                                            nsIDOMDocumentFragment** aReturn);
   static already_AddRefed<mozilla::dom::DocumentFragment>
   CreateContextualFragment(nsINode* aContextNode, const nsAString& aFragment,
                            bool aPreventScriptExecution,
                            mozilla::ErrorResult& aRv);
   /**
    * Invoke the fragment parsing algorithm (innerHTML) using the HTML parser.
    *
    * @param aSourceBuffer the string being set as innerHTML
    * @param aTargetNode the target container
    * @param aContextLocalName local name of context node
    * @param aContextNamespace namespace of context node
    * @param aQuirks true to make <table> not close <p>
    * @param aPreventScriptExecution true to prevent scripts from executing;
    *        don't set to false when parsing into a target node that has been
    *        bound to tree.
    * @return NS_ERROR_DOM_INVALID_STATE_ERR if a re-entrant attempt to parse
    *         fragments is made, NS_ERROR_OUT_OF_MEMORY if aSourceBuffer is too
    *         long and NS_OK otherwise.
    */
   static nsresult ParseFragmentHTML(const nsAString& aSourceBuffer,
                                     nsIContent* aTargetNode,
                                     nsIAtom* aContextLocalName,
                                     int32_t aContextNamespace,
                                     bool aQuirks,
                                     bool aPreventScriptExecution);
   /**
    * Invoke the fragment parsing algorithm (innerHTML) using the XML parser.
    *
    * @param aSourceBuffer the string being set as innerHTML
    * @param aTargetNode the target container
    * @param aTagStack the namespace mapping context
    * @param aPreventExecution whether to mark scripts as already started
    * @param aReturn the result fragment
    * @return NS_ERROR_DOM_INVALID_STATE_ERR if a re-entrant attempt to parse
    *         fragments is made, a return code from the XML parser.
    */
   static nsresult ParseFragmentXML(const nsAString& aSourceBuffer,
                                    nsIDocument* aDocument,
                                    nsTArray<nsString>& aTagStack,
                                    bool aPreventScriptExecution,
                                    nsIDOMDocumentFragment** aReturn);
   /**
    * Parse a string into a document using the HTML parser.
    * Script elements are marked unexecutable.
    *
    * @param aSourceBuffer the string to parse as an HTML document
    * @param aTargetDocument the document object to parse into. Must not have
    *                        child nodes.
    * @param aScriptingEnabledForNoscriptParsing whether <noscript> is parsed
    *                                            as if scripting was enabled
    * @return NS_ERROR_DOM_INVALID_STATE_ERR if a re-entrant attempt to parse
    *         fragments is made, NS_ERROR_OUT_OF_MEMORY if aSourceBuffer is too
    *         long and NS_OK otherwise.
    */
   static nsresult ParseDocumentHTML(const nsAString& aSourceBuffer,
                                     nsIDocument* aTargetDocument,
                                     bool aScriptingEnabledForNoscriptParsing);
   /**
    * Converts HTML source to plain text by parsing the source and using the
    * plain text serializer on the resulting tree.
    *
    * @param aSourceBuffer the string to parse as an HTML document
    * @param aResultBuffer the string where the plain text result appears;
    *                      may be the same string as aSourceBuffer
    * @param aFlags Flags from nsIDocumentEncoder.
    * @param aWrapCol Number of columns after which to line wrap; 0 for no
    *                 auto-wrapping
    * @return NS_ERROR_DOM_INVALID_STATE_ERR if a re-entrant attempt to parse
    *         fragments is made, NS_ERROR_OUT_OF_MEMORY if aSourceBuffer is too
    *         long and NS_OK otherwise.
    */
   static nsresult ConvertToPlainText(const nsAString& aSourceBuffer,
                                      nsAString& aResultBuffer,
                                      uint32_t aFlags,
                                      uint32_t aWrapCol);
   /**
    * Sets the text contents of a node by replacing all existing children
    * with a single text child.
    *
    * The function always notifies.
    *
    * Will reuse the first text child if one is available. Will not reuse
    * existing cdata children.
    *
    * @param aContent Node to set contents of.
    * @param aValue   Value to set contents to.
    * @param aTryReuse When true, the function will try to reuse an existing
    *                  textnodes rather than always creating a new one.
    */
   static nsresult SetNodeTextContent(nsIContent* aContent,
                                      const nsAString& aValue,
                                      bool aTryReuse);
   /**
    * Get the textual contents of a node. This is a concatenation of all
    * textnodes that are direct or (depending on aDeep) indirect children
    * of the node.
    *
    * NOTE! No serialization takes place and <br> elements
    * are not converted into newlines. Only textnodes and cdata nodes are
    * added to the result.
    *
    * @param aNode Node to get textual contents of.
    * @param aDeep If true child elements of aNode are recursivly descended
    *              into to find text children.
    * @param aResult the result. Out param.
    * @return false on out of memory errors, true otherwise.
    */
   static bool GetNodeTextContent(nsINode* aNode, bool aDeep,
                                  nsAString& aResult) NS_WARN_UNUSED_RESULT;
   /**
    * Same as GetNodeTextContents but appends the result rather than sets it.
    */
   static bool AppendNodeTextContent(nsINode* aNode, bool aDeep,
                                     nsAString& aResult, const mozilla::fallible_t&);
   /**
    * Utility method that checks if a given node has any non-empty
    * children.
    * NOTE! This method does not descend recursivly into elements.
    * Though it would be easy to make it so if needed
    */
   static bool HasNonEmptyTextContent(nsINode* aNode);
   /**
    * Delete strings allocated for nsContentList matches
    */
   static void DestroyMatchString(void* aData);
   /**
    * Unbinds the content from the tree and nulls it out if it's not null.
    */
   static void DestroyAnonymousContent(nsCOMPtr<nsIContent>* aContent);
   static void DestroyAnonymousContent(nsCOMPtr<Element>* aElement);
   static void DeferredFinalize(nsISupports* aSupports);
   static void DeferredFinalize(mozilla::DeferredFinalizeAppendFunction aAppendFunc,
                                mozilla::DeferredFinalizeFunction aFunc,
                                void* aThing);
   /*
    * Notify when the first XUL menu is opened and when the all XUL menus are
    * closed. At opening, aInstalling should be TRUE, otherwise, it should be
    * FALSE.
    */
   static void NotifyInstalledMenuKeyboardListener(bool aInstalling);
   /**
    * Do security checks before loading a resource. Does the following checks:
    *   nsIScriptSecurityManager::CheckLoadURIWithPrincipal
    *   NS_CheckContentLoadPolicy
    *   nsIScriptSecurityManager::CheckSameOriginURI
    *
    * You will still need to do at least SameOrigin checks before on redirects.
    *
    * @param aURIToLoad         URI that is getting loaded.
    * @param aLoadingPrincipal  Principal of the resource that is initiating
    *                           the load
    * @param aCheckLoadFlags    Flags to be passed to
    *                           nsIScriptSecurityManager::CheckLoadURIWithPrincipal
    *                           NOTE: If this contains ALLOW_CHROME the
    *                                 CheckSameOriginURI check will be skipped if
    *                                 aURIToLoad is a chrome uri.
    * @param aAllowData         Set to true to skip CheckSameOriginURI check when
                                aURIToLoad is a data uri.
    * @param aContentPolicyType Type     \
    * @param aContext           Context   |- to be passed to
    * @param aMimeGuess         Mimetype  |      NS_CheckContentLoadPolicy
    * @param aExtra             Extra    /
    */
   static nsresult CheckSecurityBeforeLoad(nsIURI* aURIToLoad,
                                           nsIPrincipal* aLoadingPrincipal,
                                           uint32_t aCheckLoadFlags,
                                           bool aAllowData,
                                           uint32_t aContentPolicyType,
                                           nsISupports* aContext,
                                           const nsAFlatCString& aMimeGuess = EmptyCString(),
                                           nsISupports* aExtra = nullptr);
   /**
    * Returns true if aPrincipal is the system principal.
    */
   static bool IsSystemPrincipal(nsIPrincipal* aPrincipal);
   /**
    * Returns true if aPrincipal is an nsExpandedPrincipal.
    */
   static bool IsExpandedPrincipal(nsIPrincipal* aPrincipal);
   /**
    * Returns true if aPrincipal is the system or an nsExpandedPrincipal.
    */
   static bool IsSystemOrExpandedPrincipal(nsIPrincipal* aPrincipal)
   {
     return IsSystemPrincipal(aPrincipal) || IsExpandedPrincipal(aPrincipal);
   }
   /**
    * Gets the system principal from the security manager.
    */
   static nsIPrincipal* GetSystemPrincipal();
   /**
    * *aResourcePrincipal is a principal describing who may access the contents
    * of a resource. The resource can only be consumed by a principal that
    * subsumes *aResourcePrincipal. MAKE SURE THAT NOTHING EVER ACTS WITH THE
    * AUTHORITY OF *aResourcePrincipal.
    * It may be null to indicate that the resource has no data from any origin
    * in it yet and anything may access the resource.
    * Additional data is being mixed into the resource from aExtraPrincipal
    * (which may be null; if null, no data is being mixed in and this function
    * will do nothing). Update *aResourcePrincipal to reflect the new data.
    * If *aResourcePrincipal subsumes aExtraPrincipal, nothing needs to change,
    * otherwise *aResourcePrincipal is replaced with the system principal.
    * Returns true if *aResourcePrincipal changed.
    */
   static bool CombineResourcePrincipals(nsCOMPtr<nsIPrincipal>* aResourcePrincipal,
                                         nsIPrincipal* aExtraPrincipal);
   /**
    * Trigger a link with uri aLinkURI. If aClick is false, this triggers a
    * mouseover on the link, otherwise it triggers a load after doing a
    * security check using aContent's principal.
    *
    * @param aContent the node on which a link was triggered.
    * @param aPresContext the pres context, must be non-null.
    * @param aLinkURI the URI of the link, must be non-null.
    * @param aTargetSpec the target (like target=, may be empty).
    * @param aClick whether this was a click or not (if false, this method
    *               assumes you just hovered over the link).
    * @param aIsUserTriggered whether the user triggered the link. This would be
    *                         false for loads from auto XLinks or from the
    *                         click() method if we ever implement it.
    * @param aIsTrusted If false, JS Context will be pushed to stack
    *                   when the link is triggered.
    */
   static void TriggerLink(nsIContent *aContent, nsPresContext *aPresContext,
                           nsIURI *aLinkURI, const nsString& aTargetSpec,
                           bool aClick, bool aIsUserTriggered,
                           bool aIsTrusted);
   /**
    * Get the link location.
    */
   static void GetLinkLocation(mozilla::dom::Element* aElement,
                               nsString& aLocationString);
   /**
    * Return top-level widget in the parent chain.
    */
   static nsIWidget* GetTopLevelWidget(nsIWidget* aWidget);
   /**
    * Return the localized ellipsis for UI.
    */
   static const nsDependentString GetLocalizedEllipsis();
   /**
    * Get the candidates for accelkeys for aDOMKeyEvent.
    *
    * @param aDOMKeyEvent [in] the key event for accelkey handling.
    * @param aCandidates [out] the candidate shortcut key combination list.
    *                          the first item is most preferred.
    */
   static void GetAccelKeyCandidates(nsIDOMKeyEvent* aDOMKeyEvent,
                                     nsTArray<nsShortcutCandidate>& aCandidates);
   /**
    * Get the candidates for accesskeys for aNativeKeyEvent.
    *
    * @param aNativeKeyEvent [in] the key event for accesskey handling.
    * @param aCandidates [out] the candidate access key list.
    *                          the first item is most preferred.
    */
   static void GetAccessKeyCandidates(
                 mozilla::WidgetKeyboardEvent* aNativeKeyEvent,
                 nsTArray<uint32_t>& aCandidates);
   /**
    * Hide any XUL popups associated with aDocument, including any documents
    * displayed in child frames. Does nothing if aDocument is null.
    */
   static void HidePopupsInDocument(nsIDocument* aDocument);
   /**
    * Retrieve the current drag session, or null if no drag is currently occuring
    */
   static already_AddRefed<nsIDragSession> GetDragSession();
   /*
    * Initialize and set the dataTransfer field of an WidgetDragEvent.
    */
   static nsresult SetDataTransferInEvent(mozilla::WidgetDragEvent* aDragEvent);
   // filters the drag and drop action to fit within the effects allowed and
   // returns it.
   static uint32_t FilterDropEffect(uint32_t aAction, uint32_t aEffectAllowed);
   /*
    * Return true if the target of a drop event is a content document that is
    * an ancestor of the document for the source of the drag.
    */
   static bool CheckForSubFrameDrop(nsIDragSession* aDragSession,
                                    mozilla::WidgetDragEvent* aDropEvent);
   /**
    * Return true if aURI is a local file URI (i.e. file://).
    */
   static bool URIIsLocalFile(nsIURI *aURI);
   /**
    * Given a URI, return set beforeHash to the part before the '#', and
    * afterHash to the remainder of the URI, including the '#'.
    */
   static nsresult SplitURIAtHash(nsIURI *aURI,
                                  nsACString &aBeforeHash,
                                  nsACString &aAfterHash);
   /**
    * Get the application manifest URI for this document.  The manifest URI
    * is specified in the manifest= attribute of the root element of the
    * document.
    *
    * @param aDocument The document that lists the manifest.
    * @param aURI The manifest URI.
    */
   static void GetOfflineAppManifest(nsIDocument *aDocument, nsIURI **aURI);
   /**
    * Check whether an application should be allowed to use offline APIs.
    */
   static bool OfflineAppAllowed(nsIURI *aURI);
   /**
    * Check whether an application should be allowed to use offline APIs.
    */
   static bool OfflineAppAllowed(nsIPrincipal *aPrincipal);
   /**
    * If offline-apps.allow_by_default is true, we set offline-app permission
    * for the principal and return true.  Otherwise false.
    */
   static bool MaybeAllowOfflineAppByDefault(nsIPrincipal *aPrincipal, nsIDOMWindow *aWindow);
   /**
    * Increases the count of blockers preventing scripts from running.
    * NOTE: You might want to use nsAutoScriptBlocker rather than calling
    * this directly
    */
   static void AddScriptBlocker();
   /**
    * Decreases the count of blockers preventing scripts from running.
    * NOTE: You might want to use nsAutoScriptBlocker rather than calling
    * this directly
    *
    * WARNING! Calling this function could synchronously execute scripts.
    */
   static void RemoveScriptBlocker();
   /**
    * Add a runnable that is to be executed as soon as it's safe to execute
    * scripts.
    * NOTE: If it's currently safe to execute scripts, aRunnable will be run
    *       synchronously before the function returns.
    *
    * @param aRunnable  The nsIRunnable to run as soon as it's safe to execute
    *                   scripts. Passing null is allowed and results in nothing
    *                   happening. It is also allowed to pass an object that
    *                   has not yet been AddRefed.
    * @return false on out of memory, true otherwise.
    */
   static bool AddScriptRunner(nsIRunnable* aRunnable);
   /**
    * Returns true if it's safe to execute content script and false otherwise.
    *
    * The only known case where this lies is mutation events. They run, and can
    * run anything else, when this function returns false, but this is ok.
    */
   static bool IsSafeToRunScript() {
     return sScriptBlockerCount == 0;
   }
   /**
    * Retrieve information about the viewport as a data structure.
    * This will return information in the viewport META data section
    * of the document. This can be used in lieu of ProcessViewportInfo(),
    * which places the viewport information in the document header instead
    * of returning it directly.
    *
    * @param aDisplayWidth width of the on-screen display area for this
    * document, in device pixels.
    * @param aDisplayHeight height of the on-screen display area for this
    * document, in device pixels.
    *
    * NOTE: If the site is optimized for mobile (via the doctype), this
    * will return viewport information that specifies default information.
    */
   static nsViewportInfo GetViewportInfo(nsIDocument* aDocument,
                                         const mozilla::ScreenIntSize& aDisplaySize);
   // Call EnterMicroTask when you're entering JS execution.
   // Usually the best way to do this is to use nsAutoMicroTask.
   static void EnterMicroTask();
   static void LeaveMicroTask();
   static bool IsInMicroTask();
   static uint32_t MicroTaskLevel();
   static void SetMicroTaskLevel(uint32_t aLevel);
   /* Process viewport META data. This gives us information for the scale
    * and zoom of a page on mobile devices. We stick the information in
    * the document header and use it later on after rendering.
    *
    * See Bug #436083
    */
   static nsresult ProcessViewportInfo(nsIDocument *aDocument,
                                       const nsAString &viewportInfo);
   static nsIScriptContext* GetContextForEventHandlers(nsINode* aNode,
                                                       nsresult* aRv);
   static JSContext *GetCurrentJSContext();
   static JSContext *GetSafeJSContext();
   static JSContext *GetCurrentJSContextForThread();
   static JSContext *GetDefaultJSContextForThread();
   /**
    * Case insensitive comparison between two strings. However it only ignores
    * case for ASCII characters a-z.
    */
   static bool EqualsIgnoreASCIICase(const nsAString& aStr1,
                                     const nsAString& aStr2);
   /**
    * Convert ASCII A-Z to a-z.
    * @return NS_OK on success, or NS_ERROR_OUT_OF_MEMORY if making the string
    * writable needs to allocate memory and that allocation fails.
    */
   static nsresult ASCIIToLower(nsAString& aStr);
   static nsresult ASCIIToLower(const nsAString& aSource, nsAString& aDest);
   /**
    * Convert ASCII a-z to A-Z.
    * @return NS_OK on success, or NS_ERROR_OUT_OF_MEMORY if making the string
    * writable needs to allocate memory and that allocation fails.
    */
   static nsresult ASCIIToUpper(nsAString& aStr);
   static nsresult ASCIIToUpper(const nsAString& aSource, nsAString& aDest);
   /**
    * Return whether aStr contains an ASCII uppercase character.
    */
   static bool StringContainsASCIIUpper(const nsAString& aStr);
   // Returns NS_OK for same origin, error (NS_ERROR_DOM_BAD_URI) if not.
   static nsresult CheckSameOrigin(nsIChannel *aOldChannel, nsIChannel *aNewChannel);
   static nsIInterfaceRequestor* GetSameOriginChecker();
   // Trace the safe JS context.
   static void TraceSafeJSContext(JSTracer* aTrc);
   /**
    * Get the Origin of the passed in nsIPrincipal or nsIURI. If the passed in
    * nsIURI or the URI of the passed in nsIPrincipal does not have a host, the
    * origin is set to 'null'.
    *
    * The ASCII versions return a ASCII strings that are puny-code encoded,
    * suitable for, for example, header values. The UTF versions return strings
    * containing international characters.
    *
    * @pre aPrincipal/aOrigin must not be null.
    *
    * @note this should be used for HTML5 origin determination.
    */
   static nsresult GetASCIIOrigin(nsIPrincipal* aPrincipal,
                                  nsCString& aOrigin);
   static nsresult GetASCIIOrigin(nsIURI* aURI, nsCString& aOrigin);
   static nsresult GetUTFOrigin(nsIPrincipal* aPrincipal,
                                nsString& aOrigin);
   static nsresult GetUTFOrigin(nsIURI* aURI, nsString& aOrigin);
   static void GetUTFNonNullOrigin(nsIURI* aURI, nsString& aOrigin);
   /**
    * This method creates and dispatches "command" event, which implements
    * nsIDOMXULCommandEvent.
    * If aShell is not null, dispatching goes via
    * nsIPresShell::HandleDOMEventWithTarget.
    */
   static nsresult DispatchXULCommand(nsIContent* aTarget,
                                      bool aTrusted,
                                      nsIDOMEvent* aSourceEvent = nullptr,
                                      nsIPresShell* aShell = nullptr,
                                      bool aCtrl = false,
                                      bool aAlt = false,
                                      bool aShift = false,
                                      bool aMeta = false);
   /**
    * Gets the nsIDocument given the script context. Will return nullptr on failure.
    *
    * @param aScriptContext the script context to get the document for; can be null
    *
    * @return the document associated with the script context
    */
   static nsIDocument*
   GetDocumentFromScriptContext(nsIScriptContext* aScriptContext);
   static bool CheckMayLoad(nsIPrincipal* aPrincipal, nsIChannel* aChannel, bool aAllowIfInheritsPrincipal);
   /**
    * The method checks whether the caller can access native anonymous content.
    * If there is no JS in the stack or privileged JS is running, this
    * method returns true, otherwise false.
    */
   static bool CanAccessNativeAnon();
   MOZ_WARN_UNUSED_RESULT
   static nsresult WrapNative(JSContext *cx, nsISupports *native,
                              const nsIID* aIID, JS::MutableHandle<JS::Value> vp,
                              bool aAllowWrapping = true)
   {
     return WrapNative(cx, native, nullptr, aIID, vp, aAllowWrapping);
   }
   // Same as the WrapNative above, but use this one if aIID is nsISupports' IID.
   MOZ_WARN_UNUSED_RESULT
   static nsresult WrapNative(JSContext *cx, nsISupports *native,
                              JS::MutableHandle<JS::Value> vp,
                              bool aAllowWrapping = true)
   {
     return WrapNative(cx, native, nullptr, nullptr, vp, aAllowWrapping);
   }
   MOZ_WARN_UNUSED_RESULT
   static nsresult WrapNative(JSContext *cx, nsISupports *native,
                              nsWrapperCache *cache,
                              JS::MutableHandle<JS::Value> vp,
                              bool aAllowWrapping = true)
   {
     return WrapNative(cx, native, cache, nullptr, vp, aAllowWrapping);
   }
   /**
    * Creates an arraybuffer from a binary string.
    */
   static nsresult CreateArrayBuffer(JSContext *aCx, const nsACString& aData,
                                     JSObject** aResult);
   static nsresult CreateBlobBuffer(JSContext* aCx,
                                    const nsACString& aData,
                                    JS::MutableHandle<JS::Value> aBlob);
   static void StripNullChars(const nsAString& aInStr, nsAString& aOutStr);
   /**
    * Strip all \n, \r and nulls from the given string
    * @param aString the string to remove newlines from [in/out]
    */
   static void RemoveNewlines(nsString &aString);
   /**
    * Convert Windows and Mac platform linebreaks to \n.
    * @param aString the string to convert the newlines inside [in/out]
    */
   static void PlatformToDOMLineBreaks(nsString &aString);
   /**
    * Populates aResultString with the contents of the string-buffer aBuf, up
    * to aBuf's null-terminator.  aBuf must not be null. Ownership of the string
    * is not transferred.
    */
   static void PopulateStringFromStringBuffer(nsStringBuffer* aBuf,
                                              nsAString& aResultString);
   static bool IsHandlingKeyBoardEvent()
   {
     return sIsHandlingKeyBoardEvent;
   }
   static void SetIsHandlingKeyBoardEvent(bool aHandling)
   {
     sIsHandlingKeyBoardEvent = aHandling;
   }
   /**
    * Utility method for getElementsByClassName.  aRootNode is the node (either
    * document or element), which getElementsByClassName was called on.
    */
   static already_AddRefed<nsContentList>
   GetElementsByClassName(nsINode* aRootNode, const nsAString& aClasses)
   {
     NS_PRECONDITION(aRootNode, "Must have root node");
     return NS_GetFuncStringHTMLCollection(aRootNode, MatchClassNames,
                                           DestroyClassNameArray,
                                           AllocClassMatchingInfo,
                                           aClasses);
   }
   /**
    * Returns a presshell for this document, if there is one. This will be
    * aDoc's direct presshell if there is one, otherwise we'll look at all
    * ancestor documents to try to find a presshell, so for example this can
    * still find a presshell for documents in display:none frames that have
    * no presentation. So you have to be careful how you use this presshell ---
    * getting generic data like a device context or widget from it is OK, but it
    * might not be this document's actual presentation.
    */
   static nsIPresShell* FindPresShellForDocument(const nsIDocument* aDoc);
   /**
    * Returns the widget for this document if there is one. Looks at all ancestor
    * documents to try to find a widget, so for example this can still find a
    * widget for documents in display:none frames that have no presentation.
    */
   static nsIWidget* WidgetForDocument(const nsIDocument* aDoc);
   /**
    * Returns a layer manager to use for the given document. Basically we
    * look up the document hierarchy for the first document which has
    * a presentation with an associated widget, and use that widget's
    * layer manager.
    *
    * @param aDoc the document for which to return a layer manager.
    * @param aAllowRetaining an outparam that states whether the returned
    * layer manager should be used for retained layers
    */
   static already_AddRefed<mozilla::layers::LayerManager>
   LayerManagerForDocument(const nsIDocument *aDoc, bool *aAllowRetaining = nullptr);
   /**
    * Returns a layer manager to use for the given document. Basically we
    * look up the document hierarchy for the first document which has
    * a presentation with an associated widget, and use that widget's
    * layer manager. In addition to the normal layer manager lookup this will
    * specifically request a persistent layer manager. This means that the layer
    * manager is expected to remain the layer manager for the document in the
    * forseeable future. This function should be used carefully as it may change
    * the document's layer manager.
    *
    * @param aDoc the document for which to return a layer manager.
    * @param aAllowRetaining an outparam that states whether the returned
    * layer manager should be used for retained layers
    */
   static already_AddRefed<mozilla::layers::LayerManager>
   PersistentLayerManagerForDocument(nsIDocument *aDoc, bool *aAllowRetaining = nullptr);
   /**
    * Determine whether a content node is focused or not,
    *
    * @param aContent the content node to check
    * @return true if the content node is focused, false otherwise.
    */
   static bool IsFocusedContent(const nsIContent *aContent);
   /**
    * Returns true if the DOM full-screen API is enabled.
    */
   static bool IsFullScreenApiEnabled();
   /**
    * Returns true if requests for full-screen are allowed in the current
    * context. Requests are only allowed if the user initiated them (like with
    * a mouse-click or key press), unless this check has been disabled by
    * setting the pref "full-screen-api.allow-trusted-requests-only" to false.
    */
   static bool IsRequestFullScreenAllowed();
   /**
    * Returns true if the DOM fullscreen API is restricted to content only.
    * This mirrors the pref "full-screen-api.content-only". If this is true,
    * fullscreen requests in chrome are denied, and fullscreen requests in
    * content stop percolating upwards before they reach chrome documents.
    * That is, when an element in content requests fullscreen, only its
    * containing frames that are in content are also made fullscreen, not
    * the containing frame in the chrome document.
    *
    * Note if the fullscreen API is running in content only mode then multiple
    * branches of a doctree can be fullscreen at the same time, but no fullscreen
    * document will have a common ancestor with another fullscreen document
    * that is also fullscreen (since the only common ancestor they can have
    * is the chrome document, and that can't be fullscreen). i.e. multiple
    * child documents of the chrome document can be fullscreen, but the chrome
    * document won't be fullscreen.
    *
    * Making the fullscreen API content only is useful on platforms where we
    * still want chrome to be visible or accessible while content is
    * fullscreen, like on Windows 8 in Metro mode.
    *
    * Note that if the fullscreen API is content only, chrome can still go
    * fullscreen by setting the "fullScreen" attribute on its XUL window.
    */
   static bool IsFullscreenApiContentOnly();
   /**
    * Returns true if the idle observers API is enabled.
    */
   static bool IsIdleObserverAPIEnabled() { return sIsIdleObserverAPIEnabled; }
   /*
    * Returns true if the performance timing APIs are enabled.
    */
   static bool IsPerformanceTimingEnabled()
   {
     return sIsPerformanceTimingEnabled;
   }
   /*
    * Returns true if the performance timing APIs are enabled.
    */
   static bool IsResourceTimingEnabled()
   {
     return sIsResourceTimingEnabled;
   }
   /**
    * Returns true if the doc tree branch which contains aDoc contains any
    * plugins which we don't control event dispatch for, i.e. do any plugins
    * in the same tab as this document receive key events outside of our
    * control? This always returns false on MacOSX.
    */
   static bool HasPluginWithUncontrolledEventDispatch(nsIDocument* aDoc);
   /**
    * Fire mutation events for changes caused by parsing directly into a
    * context node.
    *
    * @param aDoc the document of the node
    * @param aDest the destination node that got stuff appended to it
    * @param aOldChildCount the number of children the node had before parsing
    */
   static void FireMutationEventsForDirectParsing(nsIDocument* aDoc,
                                                  nsIContent* aDest,
                                                  int32_t aOldChildCount);
   /**
    * Returns true if the content is in a document and contains a plugin
    * which we don't control event dispatch for, i.e. do any plugins in this
    * doc tree receive key events outside of our control? This always returns
    * false on MacOSX.
    */
   static bool HasPluginWithUncontrolledEventDispatch(nsIContent* aContent);
   /**
    * Returns the document that is the closest ancestor to aDoc that is
    * fullscreen. If aDoc is fullscreen this returns aDoc. If aDoc is not
    * fullscreen and none of aDoc's ancestors are fullscreen this returns
    * nullptr.
    */
   static nsIDocument* GetFullscreenAncestor(nsIDocument* aDoc);
   /**
    * Returns true if aWin and the current pointer lock document
    * have common scriptable top window.
    */
   static bool IsInPointerLockContext(nsIDOMWindow* aWin);
   /**
    * Returns the time limit on handling user input before
    * EventStateManager::IsHandlingUserInput() stops returning true.
    * This enables us to detect long running user-generated event handlers.
    */
   static TimeDuration HandlingUserInputTimeout();
   static void GetShiftText(nsAString& text);
   static void GetControlText(nsAString& text);
   static void GetMetaText(nsAString& text);
   static void GetOSText(nsAString& text);
   static void GetAltText(nsAString& text);
   static void GetModifierSeparatorText(nsAString& text);
   /**
    * Returns if aContent has a tabbable subdocument.
    * A sub document isn't tabbable when it's a zombie document.
    *
    * @param aElement element to test.
    *
    * @return Whether the subdocument is tabbable.
    */
   static bool IsSubDocumentTabbable(nsIContent* aContent);
   /**
    * Returns if aNode ignores user focus.
    *
    * @param aNode node to test
    *
    * @return Whether the node ignores user focus.
    */
   static bool IsUserFocusIgnored(nsINode* aNode);
   /**
    * Returns if aContent has the 'scrollgrab' property.
    * aContent may be null (in this case false is returned).
    */
   static bool HasScrollgrab(nsIContent* aContent);
   /**
    * Flushes the layout tree (recursively)
    *
    * @param aWindow the window the flush should start at
    *
    */
   static void FlushLayoutForTree(nsIDOMWindow* aWindow);
   /**
    * Returns true if content with the given principal is allowed to use XUL
    * and XBL and false otherwise.
    */
   static bool AllowXULXBLForPrincipal(nsIPrincipal* aPrincipal);
   /**
    * Perform cleanup that's appropriate for XPCOM shutdown.
    */
   static void XPCOMShutdown();
   enum ContentViewerType
   {
       TYPE_UNSUPPORTED,
       TYPE_CONTENT,
       TYPE_PLUGIN,
       TYPE_UNKNOWN
   };
   static already_AddRefed<nsIDocumentLoaderFactory>
   FindInternalContentViewer(const char* aType,
                             ContentViewerType* aLoaderType = nullptr);
   /**
    * This helper method returns true if the aPattern pattern matches aValue.
    * aPattern should not contain leading and trailing slashes (/).
    * The pattern has to match the entire value not just a subset.
    * aDocument must be a valid pointer (not null).
    *
    * This is following the HTML5 specification:
    * http://dev.w3.org/html5/spec/forms.html#attr-input-pattern
    *
    * WARNING: This method mutates aPattern and aValue!
    *
    * @param aValue    the string to check.
    * @param aPattern  the string defining the pattern.
    * @param aDocument the owner document of the element.
    * @result          whether the given string is matches the pattern.
    */
   static bool IsPatternMatching(nsAString& aValue, nsAString& aPattern,
                                   nsIDocument* aDocument);
   /**
    * Calling this adds support for
    * ontouch* event handler DOM attributes.
    */
   static void InitializeTouchEventTable();
   /**
    * Test whether the given URI always inherits a security context
    * from the document it comes from.
    */
   static nsresult URIInheritsSecurityContext(nsIURI *aURI, bool *aResult);
   /**
    * Set the given principal as the owner of the given channel, if
    * needed.  aURI must be the URI of aChannel.  aPrincipal may be
    * null.  If aSetUpForAboutBlank is true, then about:blank will get
    * the principal set up on it. If aForceOwner is true, the owner
    * will be set on the channel, even if the principal can be determined
    * from the channel.
    * The return value is whether the principal was set up as the owner
    * of the channel.
    */
   static bool SetUpChannelOwner(nsIPrincipal* aLoadingPrincipal,
                                 nsIChannel* aChannel,
                                 nsIURI* aURI,
                                 bool aSetUpForAboutBlank,
                                 bool aForceOwner = false);
   static nsresult Btoa(const nsAString& aBinaryData,
                        nsAString& aAsciiBase64String);
   static nsresult Atob(const nsAString& aAsciiString,
                        nsAString& aBinaryData);
   /**
    * Returns whether the input element passed in parameter has the autocomplete
    * functionality enabled. It is taking into account the form owner.
    * NOTE: the caller has to make sure autocomplete makes sense for the
    * element's type.
    *
    * @param aInput the input element to check. NOTE: aInput can't be null.
    * @return whether the input element has autocomplete enabled.
    */
   static bool IsAutocompleteEnabled(nsIDOMHTMLInputElement* aInput);
   /**
    * This will parse aSource, to extract the value of the pseudo attribute
    * with the name specified in aName. See
    * http://www.w3.org/TR/xml-stylesheet/#NT-StyleSheetPI for the specification
    * which is used to parse aSource.
    *
    * @param aSource the string to parse
    * @param aName the name of the attribute to get the value for
    * @param aValue [out] the value for the attribute with name specified in
    *                     aAttribute. Empty if the attribute isn't present.
    * @return true     if the attribute exists and was successfully parsed.
    *         false if the attribute doesn't exist, or has a malformed
    *                  value, such as an unknown or unterminated entity.
    */
   static bool GetPseudoAttributeValue(const nsString& aSource, nsIAtom *aName,
                                       nsAString& aValue);
   /**
    * Returns true if the language name is a version of JavaScript and
    * false otherwise
    */
   static bool IsJavaScriptLanguage(const nsString& aName);
   /**
    * Returns the JSVersion for a string of the form '1.n', n = 0, ..., 8, and
    * JSVERSION_UNKNOWN for other strings.
    */
   static JSVersion ParseJavascriptVersion(const nsAString& aVersionStr);
   static bool IsJavascriptMIMEType(const nsAString& aMIMEType);
   static void SplitMimeType(const nsAString& aValue, nsString& aType,
                             nsString& aParams);
   /**
    * Function checks if the user is idle.
    *
    * @param aRequestedIdleTimeInMS    The idle observer's requested idle time.
    * @param aUserIsIdle               boolean indicating if the user
    *                                  is currently idle or not.   *
    * @return NS_OK                    NS_OK returned if the requested idle service and
    *                                  the current idle time were successfully obtained.
    *                                  NS_ERROR_FAILURE returned if the the requested
    *                                  idle service or the current idle were not obtained.
    */
   static nsresult IsUserIdle(uint32_t aRequestedIdleTimeInMS, bool* aUserIsIdle);
   /**
    * Takes a selection, and a text control element (<input> or <textarea>), and
    * returns the offsets in the text content corresponding to the selection.
    * The selection's anchor and focus must both be in the root node passed or a
    * descendant.
    *
    * @param aSelection      Selection to check
    * @param aRoot           Root <input> or <textarea> element
    * @param aOutStartOffset Output start offset
    * @param aOutEndOffset   Output end offset
    */
   static void GetSelectionInTextControl(mozilla::dom::Selection* aSelection,
                                         Element* aRoot,
                                         int32_t& aOutStartOffset,
                                         int32_t& aOutEndOffset);
   /**
    * Takes a frame for anonymous content within a text control (<input> or
    * <textarea>), and returns an offset in the text content, adjusted for a
    * trailing <br> frame.
    *
    * @param aOffsetFrame      Frame for the text content in which the offset
    *                          lies
    * @param aOffset           Offset as calculated by GetContentOffsetsFromPoint
    * @param aOutOffset        Output adjusted offset
    *
    * @see GetSelectionInTextControl for the original basis of this function.
    */
   static int32_t GetAdjustedOffsetInTextControl(nsIFrame* aOffsetFrame,
                                                 int32_t aOffset);
   static nsIEditor* GetHTMLEditor(nsPresContext* aPresContext);
   /**
    * Check whether a spec feature/version is supported.
    * @param aObject the object, which should support the feature,
    *        for example nsIDOMNode or nsIDOMDOMImplementation
    * @param aFeature the feature ("Views", "Core", "HTML", "Range" ...)
    * @param aVersion the version ("1.0", "2.0", ...)
    * @return whether the feature is supported or not
    */
   static bool InternalIsSupported(nsISupports* aObject,
                                   const nsAString& aFeature,
                                   const nsAString& aVersion);
   /**
    * Return true if the browser.dom.window.dump.enabled pref is set.
    */
   static bool DOMWindowDumpEnabled();
   /**
    * Returns whether a content is an insertion point for XBL
    * bindings or web components ShadowRoot. In web components,
    * this corresponds to a <content> element that participates
    * in node distribution. In XBL this corresponds to an
    * <xbl:children> element in anonymous content.
    *
    * @param aContent The content to test for being an insertion point.
    */
   static bool IsContentInsertionPoint(const nsIContent* aContent);
 private:
   static bool InitializeEventTable();
   static nsresult EnsureStringBundle(PropertiesFile aFile);
   static bool CanCallerAccess(nsIPrincipal* aSubjectPrincipal,
                                 nsIPrincipal* aPrincipal);
   static nsresult WrapNative(JSContext *cx, nsISupports *native,
                              nsWrapperCache *cache, const nsIID* aIID,
                              JS::MutableHandle<JS::Value> vp,
                              bool aAllowWrapping);
   static nsresult DispatchEvent(nsIDocument* aDoc,
                                 nsISupports* aTarget,
                                 const nsAString& aEventName,
                                 bool aCanBubble,
                                 bool aCancelable,
                                 bool aTrusted,
                                 bool *aDefaultAction = nullptr);
   static void InitializeModifierStrings();
   static void DropFragmentParsers();
   static bool MatchClassNames(nsIContent* aContent, int32_t aNamespaceID,
                               nsIAtom* aAtom, void* aData);
   static void DestroyClassNameArray(void* aData);
   static void* AllocClassMatchingInfo(nsINode* aRootNode,
                                       const nsString* aClasses);
   static nsIXPConnect *sXPConnect;
   static nsIScriptSecurityManager *sSecurityManager;
   static nsIParserService *sParserService;
   static nsNameSpaceManager *sNameSpaceManager;
   static nsIIOService *sIOService;
   static bool sImgLoaderInitialized;
   static void InitImgLoader();
   // The following four members are initialized lazily
   static imgLoader* sImgLoader;
   static imgLoader* sPrivateImgLoader;
   static imgICache* sImgCache;
   static imgICache* sPrivateImgCache;
   static nsIConsoleService* sConsoleService;
   static nsDataHashtable<nsISupportsHashKey, EventNameMapping>* sAtomEventTable;
   static nsDataHashtable<nsStringHashKey, EventNameMapping>* sStringEventTable;
   static nsCOMArray<nsIAtom>* sUserDefinedEvents;
   static nsIStringBundleService* sStringBundleService;
   static nsIStringBundle* sStringBundles[PropertiesFile_COUNT];
   static nsIContentPolicy* sContentPolicyService;
   static bool sTriedToGetContentPolicy;
   static nsILineBreaker* sLineBreaker;
   static nsIWordBreaker* sWordBreaker;
   static nsIBidiKeyboard* sBidiKeyboard;
   static bool sInitialized;
   static uint32_t sScriptBlockerCount;
 #ifdef DEBUG
   static uint32_t sDOMNodeRemovedSuppressCount;
 #endif
   static uint32_t sMicroTaskLevel;
   // Not an nsCOMArray because removing elements from those is slower
   static nsTArray< nsCOMPtr<nsIRunnable> >* sBlockedScriptRunners;
   static uint32_t sRunnersCountAtFirstBlocker;
   static uint32_t sScriptBlockerCountWhereRunnersPrevented;
   static nsIInterfaceRequestor* sSameOriginChecker;
   static bool sIsHandlingKeyBoardEvent;
   static bool sAllowXULXBL_for_file;
   static bool sIsFullScreenApiEnabled;
   static bool sTrustedFullScreenOnly;
   static bool sFullscreenApiIsContentOnly;
   static uint32_t sHandlingInputTimeout;
   static bool sIsIdleObserverAPIEnabled;
   static bool sIsPerformanceTimingEnabled;
   static bool sIsResourceTimingEnabled;
   static nsHtml5StringParser* sHTMLFragmentParser;
   static nsIParser* sXMLFragmentParser;
   static nsIFragmentContentSink* sXMLFragmentSink;
   /**
    * True if there's a fragment parser activation on the stack.
    */
   static bool sFragmentParsingActive;
   static nsString* sShiftText;
   static nsString* sControlText;
   static nsString* sMetaText;
   static nsString* sOSText;
   static nsString* sAltText;
   static nsString* sModifierSeparator;
 #if !(defined(DEBUG) || defined(MOZ_ENABLE_JS_DUMP))
   static bool sDOMWindowDumpEnabled;
 #endif
 };
 class MOZ_STACK_CLASS nsAutoScriptBlocker {
 public:
   nsAutoScriptBlocker(MOZ_GUARD_OBJECT_NOTIFIER_ONLY_PARAM) {
     MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     nsContentUtils::AddScriptBlocker();
   }
   ~nsAutoScriptBlocker() {
     nsContentUtils::RemoveScriptBlocker();
   }
 private:
   MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 class MOZ_STACK_CLASS nsAutoScriptBlockerSuppressNodeRemoved :
                           public nsAutoScriptBlocker {
 public:
   nsAutoScriptBlockerSuppressNodeRemoved() {
 #ifdef DEBUG
     ++nsContentUtils::sDOMNodeRemovedSuppressCount;
 #endif
   }
   ~nsAutoScriptBlockerSuppressNodeRemoved() {
 #ifdef DEBUG
     --nsContentUtils::sDOMNodeRemovedSuppressCount;
 #endif
   }
 };
 class MOZ_STACK_CLASS nsAutoMicroTask
 {
 public:
   nsAutoMicroTask()
   {
     nsContentUtils::EnterMicroTask();
   }
   ~nsAutoMicroTask()
   {
     nsContentUtils::LeaveMicroTask();
   }
 };
 namespace mozilla {
 namespace dom {
 class TreeOrderComparator {
 public:
   bool Equals(nsINode* aElem1, nsINode* aElem2) const {
     return aElem1 == aElem2;
   }
   bool LessThan(nsINode* aElem1, nsINode* aElem2) const {
     return nsContentUtils::PositionIsBefore(aElem1, aElem2);
   }
 };
 } // namespace dom
 } // namespace mozilla
 #define NS_INTERFACE_MAP_ENTRY_TEAROFF(_interface, _allocator)                \
   if (aIID.Equals(NS_GET_IID(_interface))) {                                  \
     foundInterface = static_cast<_interface *>(_allocator);                   \
     if (!foundInterface) {                                                    \
       *aInstancePtr = nullptr;                                                 \
       return NS_ERROR_OUT_OF_MEMORY;                                          \
     }                                                                         \
   } else
 /*
  * In the following helper macros we exploit the fact that the result of a
  * series of additions will not be finite if any one of the operands in the
  * series is not finite.
  */
 #define NS_ENSURE_FINITE(f, rv)                                               \
   if (!NS_finite(f)) {                                                        \
     return (rv);                                                              \
   }
 #define NS_ENSURE_FINITE2(f1, f2, rv)                                         \
   if (!NS_finite((f1)+(f2))) {                                                \
     return (rv);                                                              \
   }
 #define NS_ENSURE_FINITE4(f1, f2, f3, f4, rv)                                 \
   if (!NS_finite((f1)+(f2)+(f3)+(f4))) {                                      \
     return (rv);                                                              \
   }
 #define NS_ENSURE_FINITE5(f1, f2, f3, f4, f5, rv)                             \
   if (!NS_finite((f1)+(f2)+(f3)+(f4)+(f5))) {                                 \
     return (rv);                                                              \
   }
 #define NS_ENSURE_FINITE6(f1, f2, f3, f4, f5, f6, rv)                         \
   if (!NS_finite((f1)+(f2)+(f3)+(f4)+(f5)+(f6))) {                            \
     return (rv);                                                              \
   }
 // Deletes a linked list iteratively to avoid blowing up the stack (bug 460444).
 #define NS_CONTENT_DELETE_LIST_MEMBER(type_, ptr_, member_)                   \
   {                                                                           \
     type_ *cur = (ptr_)->member_;                                             \
     (ptr_)->member_ = nullptr;                                                 \
     while (cur) {                                                             \
       type_ *next = cur->member_;                                             \
       cur->member_ = nullptr;                                                  \
       delete cur;                                                             \
       cur = next;                                                             \
     }                                                                         \
   }
 #endif /* nsContentUtils_h___ */

The Tor Browser / annotate

content/base/public/nsContentUtils.h@6474c204b198 (annotated)

content/base/public/nsContentUtils.h