Oilpan: Remove guardRef and guardDeref from TreeScope.

Source/core/dom/Document.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
@@ skipping 197 matching lines @@
     PluginDocumentClass = 1 << 3,
     MediaDocumentClass = 1 << 4,
     SVGDocumentClass = 1 << 5,
     XMLDocumentClass = 1 << 6,
 };
 
 typedef unsigned char DocumentClassFlags;
 
 class Document;
 
-class DocumentVisibilityObserver {
+class DocumentVisibilityObserver : public WillBeGarbageCollectedMixin {
 public:
     DocumentVisibilityObserver(Document&);
     virtual ~DocumentVisibilityObserver();
 
     virtual void didChangeVisibilityState(PageVisibilityState) = 0;
 
     // Classes that inherit Node and DocumentVisibilityObserver must have a
     // virtual override of Node::didMoveToNewDocument that calls
     // DocumentVisibilityObserver::setDocument
     void setObservedDocument(Document&);
 
 private:
     void registerObserver(Document&);
     void unregisterObserver();
     Document* m_document;

[haraken, 2014/04/25 14:30:32]

Just to confirm: This raw pointer looks safe because it's cleared in
HTMLCanvasElement::didMoveToNewDocument (if the HTMLCanvasElement moves to
another document) or the HTMLCanvasElement and the Document die together
(otherwise). Either way, DocumentVisibilityObserver doesn't outlive the
Document.

[Mads Ager (chromium), 2014/04/28 09:45:21]

Yes.

 };
 
 class Document : public ContainerNode, public TreeScope, public SecurityContext, public ExecutionContext, public ExecutionContextClient
     , public DocumentSupplementable, public LifecycleContext<Document> {
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(Document);
 public:
     static PassRefPtr<Document> create(const DocumentInit& initializer = DocumentInit())
     {
         return adoptRef(new Document(initializer));
     }
@@ skipping 608 matching lines @@
 
     Vector<IconURL> iconURLs(int iconTypesMask);
 
     void setUseSecureKeyboardEntryWhenActive(bool);
     bool useSecureKeyboardEntryWhenActive() const;
 
     void updateFocusAppearanceSoon(bool restorePreviousSelection);
     void cancelFocusAppearanceUpdate();
 
     // Extension for manipulating canvas drawing contexts for use in CSS
-    void getCSSCanvasContext(const String& type, const String& name, int width, int height, bool&, RefPtr<CanvasRenderingContext2D>&, bool&, RefPtr<WebGLRenderingContext>&);
+    void getCSSCanvasContext(const String& type, const String& name, int width, int height, bool&, RefPtrWillBeRawPtr<CanvasRenderingContext2D>&, bool&, RefPtrWillBeRawPtr<WebGLRenderingContext>&);
     HTMLCanvasElement& getCSSCanvasElement(const String& name);
 
     bool isDNSPrefetchEnabled() const { return m_isDNSPrefetchEnabled; }
     void parseDNSPrefetchControlHeader(const String&);
 
     // FIXME(crbug.com/305497): This should be removed once DOMWindow is an ExecutionContext.
     virtual void postTask(PassOwnPtr<ExecutionContextTask>) OVERRIDE; // Executes the task on context's thread asynchronously.
 
     virtual void tasksWereSuspended() OVERRIDE FINAL;
     virtual void tasksWereResumed() OVERRIDE FINAL;
@@ skipping 61 matching lines @@
 
     bool hasFullscreenElementStack() const { return m_hasFullscreenElementStack; }
     void setHasFullscreenElementStack() { m_hasFullscreenElementStack = true; }
 
     void webkitExitPointerLock();
     Element* webkitPointerLockElement() const;
 
     // Used to allow element that loads data without going through a FrameLoader to delay the 'load' event.
     void incrementLoadEventDelayCount() { ++m_loadEventDelayCount; }
     void decrementLoadEventDelayCount();
-    bool isDelayingLoadEvent() const { return m_loadEventDelayCount; }
+    void checkLoadEventSoon();
+    bool isDelayingLoadEvent();
     void loadPluginsSoon();
 
     PassRefPtrWillBeRawPtr<Touch> createTouch(DOMWindow*, EventTarget*, int identifier, int pageX, int pageY, int screenX, int screenY, int radiusX, int radiusY, float rotationAngle, float force) const;
     PassRefPtrWillBeRawPtr<TouchList> createTouchList(WillBeHeapVector<RefPtrWillBeMember<Touch> >&) const;
 
     const DocumentTiming& timing() const { return m_documentTiming; }
 
     int requestAnimationFrame(PassOwnPtr<RequestAnimationFrameCallback>);
     void cancelAnimationFrame(int id);
     void serviceScriptedAnimations(double monotonicAnimationStartTime);
@@ skipping 148 matching lines @@
     bool dirtyElementsForLayerUpdate();
     void updateDistributionIfNeeded();
     void updateUseShadowTreesIfNeeded();
     void evaluateMediaQueryListIfNeeded();
 
     void updateRenderTree(StyleRecalcChange);
     void updateStyle(StyleRecalcChange);
 
     void detachParser();
 
+    void clearWeakMembers(Visitor*);
+
     virtual bool isDocument() const OVERRIDE FINAL { return true; }
 
     virtual void childrenChanged(bool changedByParser = false, Node* beforeChange = 0, Node* afterChange = 0, int childCountDelta = 0) OVERRIDE;
 
     virtual String nodeName() const OVERRIDE FINAL;
     virtual NodeType nodeType() const OVERRIDE FINAL;
     virtual bool childTypeAllowed(NodeType) const OVERRIDE FINAL;
     virtual PassRefPtr<Node> cloneNode(bool deep = true) OVERRIDE FINAL;
     void cloneDataFromDocument(const Document&);
 
@@ skipping 105 matching lines @@
     static uint64_t s_globalTreeVersion;
 
     HashSet<NodeIterator*> m_nodeIterators;
     HashSet<Range*> m_ranges;
 
     unsigned short m_listenerTypes;
 
     MutationObserverOptions m_mutationObserverTypes;
 
     OwnPtrWillBePersistent<StyleEngine> m_styleEngine;
-    RefPtrWillBePersistent<StyleSheetList> m_styleSheetList;
+    RefPtrWillBeMember<StyleSheetList> m_styleSheetList;
 
     OwnPtr<FormController> m_formController;
 
     TextLinkColors m_textLinkColors;
     const OwnPtr<VisitedLinkState> m_visitedLinkState;
 
     bool m_visuallyOrdered;
     ReadyState m_readyState;
     bool m_isParsing;
 
@@ skipping 120 matching lines @@
     Document* m_templateDocumentHost; // Manually managed weakref (backpointer from m_templateDocument).
 
     Timer<Document> m_didAssociateFormControlsTimer;
     HashSet<RefPtr<Element> > m_associatedFormControls;
 
     HashSet<SVGUseElement*> m_useElementsNeedingUpdate;
     HashSet<Element*> m_layerUpdateElements;
 
     bool m_hasViewportUnits;
 
-    HashSet<DocumentVisibilityObserver*> m_visibilityObservers;
+    typedef WillBeHeapHashSet<RawPtrWillBeWeakMember<DocumentVisibilityObserver> > DocumentVisibilityObserverSet;
+    DocumentVisibilityObserverSet m_visibilityObservers;
 };
 
 inline void Document::notifyRemovePendingSheetIfNeeded()
 {
     if (m_needsNotifyRemoveAllPendingStylesheet)
         didRemoveAllPendingStylesheet();
 }
 
 inline bool Document::shouldOverrideLegacyDescription(ViewportDescription::Type origin)
 {
@@ skipping 43 matching lines @@
 inline bool Node::isDocumentNode() const
 {
     return this == document();
 }
 
 Node* eventTargetNodeForDocument(Document*);
 
 } // namespace WebCore
 
 #endif // Document_h