Oilpan: Prepare to move EventDispatchMediator to Oilpan heap.

Source/core/events/EventDispatchMediator.h

 /*
  * Copyright (C) 2011 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 24 matching lines @@
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/RefPtr.h"
 
 namespace WebCore {
 
 class Event;
 class EventDispatcher;
 class Node;
 
-class EventDispatchMediator : public RefCounted<EventDispatchMediator> {
+class EventDispatchMediator : public RefCountedWillBeGarbageCollectedFinalized<EventDispatchMediator> {
 public:
-    static PassRefPtr<EventDispatchMediator> create(PassRefPtrWillBeRawPtr<Event>);
+    static PassRefPtrWillBeRawPtr<EventDispatchMediator> create(PassRefPtrWillBeRawPtr<Event>);
     virtual ~EventDispatchMediator() { };
+    virtual void trace(Visitor*);
     virtual bool dispatchEvent(EventDispatcher*) const;
     Event* event() const { return m_event.get(); };
 
 protected:
     explicit EventDispatchMediator(PassRefPtrWillBeRawPtr<Event>);
     EventDispatchMediator() { };
     void setEvent(PassRefPtrWillBeRawPtr<Event> event) { m_event = event; };
 
 private:
-    RefPtrWillBePersistent<Event> m_event;
+    RefPtrWillBeMember<Event> m_event;
 };
 
 } // namespace WebCore
 
 #endif // EventDispatchMediator_h