Oilpan: move a page's UndoStack to the heap.

Source/core/editing/UndoStack.h

 /*
  * Copyright (C) 2009 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 22 matching lines @@
 
 #include "platform/heap/Handle.h"
 #include "wtf/Deque.h"
 #include "wtf/Forward.h"
 
 namespace WebCore {
 
 class LocalFrame;
 class UndoStep;
 
-class UndoStack {
+class UndoStack FINAL : public NoBaseWillBeGarbageCollected<UndoStack> {
+    DECLARE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(UndoStack)
 public:
-    static PassOwnPtr<UndoStack> create();
-
-    ~UndoStack();
+    static PassOwnPtrWillBeRawPtr<UndoStack> create();
 
     void registerUndoStep(PassRefPtrWillBeRawPtr<UndoStep>);
     void registerRedoStep(PassRefPtrWillBeRawPtr<UndoStep>);
     void didUnloadFrame(const LocalFrame&);
     bool canUndo() const;
     bool canRedo() const;
     void undo();
     void redo();
 
+    void trace(Visitor*);
+
 private:
     UndoStack();
 
     typedef WillBeHeapDeque<RefPtrWillBeMember<UndoStep> > UndoStepStack;
-    typedef WillBePersistentHeapDeque<RefPtrWillBeMember<UndoStep> > WillBePersistentUndoStepStack;
 
-    void filterOutUndoSteps(WillBePersistentUndoStepStack&, const LocalFrame&);
+    void filterOutUndoSteps(UndoStepStack&, const LocalFrame&);
 
     bool m_inRedo;
-    WillBePersistentUndoStepStack m_undoStack;
-    WillBePersistentUndoStepStack m_redoStack;
+    UndoStepStack m_undoStack;
+    UndoStepStack m_redoStack;
 };
 
 } // namespace WebCore
 
 #endif