Oilpan: Prepare to move AXObjectCache to the heap

Source/modules/accessibility/AXObjectCacheImpl.h

 /*
  * Copyright (C) 2014, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 37 matching lines @@
 
 struct TextMarkerData {
     AXID axID;
     Node* node;
     int offset;
     EAffinity affinity;
 };
 
 // This class should only be used from inside the accessibility directory.
 class MODULES_EXPORT AXObjectCacheImpl : public AXObjectCache {
-    WTF_MAKE_NONCOPYABLE(AXObjectCacheImpl); WTF_MAKE_FAST_ALLOCATED(AXObjectCacheImpl);
+    WTF_MAKE_NONCOPYABLE(AXObjectCacheImpl);
 public:
-    static AXObjectCache* create(Document&);
+    static PassOwnPtrWillBeRawPtr<AXObjectCache> create(Document&);
 
     explicit AXObjectCacheImpl(Document&);
     ~AXObjectCacheImpl();
+    DECLARE_VIRTUAL_TRACE();
 
     AXObject* focusedUIElementForPage(const Page*);
 
+    virtual void dispose() override;
+
     virtual void selectionChanged(Node*) override;
     virtual void childrenChanged(Node*) override;
     virtual void childrenChanged(LayoutObject*) override;
     virtual void checkedStateChanged(Node*) override;
     virtual void listboxOptionStateChanged(HTMLOptionElement*);
     virtual void listboxSelectedChildrenChanged(HTMLSelectElement*);
     virtual void listboxActiveIndexChanged(HTMLSelectElement*);
 
     virtual void remove(LayoutObject*) override;
     virtual void remove(Node*) override;
@@ skipping 129 matching lines @@
     HashMap<AXID, RefPtr<AXObject>> m_objects;
     HashMap<LayoutObject*, AXID> m_layoutObjectMapping;
     HashMap<Widget*, AXID> m_widgetObjectMapping;
     HashMap<Node*, AXID> m_nodeObjectMapping;
     HashMap<AbstractInlineTextBox*, AXID> m_inlineTextBoxObjectMapping;
     HashSet<Node*> m_textMarkerNodes;
     int m_modificationCount;
 
     HashSet<AXID> m_idsInUse;
 
+#if ENABLE(ASSERT)
+    // Verified when finalizing.
+    bool m_hasBeenDisposed;
+#endif
+
     //
     // Aria-owns
     //
 
     // Map from the AXID of the owner to the AXIDs of the children.
     // This is a validated map, it doesn't contain illegal, duplicate,
     // or cyclical matches, or references to IDs that don't exist.
     HashMap<AXID, Vector<AXID>> m_ariaOwnerToChildrenMapping;
 
     // Map from the AXID of a child to the AXID of the parent that owns it.
@@ skipping 31 matching lines @@
 // This is the only subclass of AXObjectCache.
 DEFINE_TYPE_CASTS(AXObjectCacheImpl, AXObjectCache, cache, true, true);
 
 bool nodeHasRole(Node*, const String& role);
 // This will let you know if aria-hidden was explicitly set to false.
 bool isNodeAriaVisible(Node*);
 
 }
 
 #endif