Remove leak of objects between isolated worlds on custom events.

Source/core/dom/PopStateEvent.h

 /*
  * Copyright (C) 2009 Apple 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
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE, INC. ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
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  */
 
 #ifndef PopStateEvent_h
 #define PopStateEvent_h
 
-#include "bindings/v8/ScriptValue.h"
 #include "core/dom/Event.h"
 
 namespace WebCore {
 
 struct PopStateEventInit : public EventInit {
     PopStateEventInit();
 
-    ScriptValue state;
+    bool stateIsSet;
 };
 
 class History;
 class SerializedScriptValue;
 
 class PopStateEvent : public Event {
 public:
     virtual ~PopStateEvent();
     static PassRefPtr<PopStateEvent> create();
     static PassRefPtr<PopStateEvent> create(PassRefPtr<SerializedScriptValue>, PassRefPtr<History>);
     static PassRefPtr<PopStateEvent> create(const AtomicString&, const PopStateEventInit&);
 
     PassRefPtr<SerializedScriptValue> serializedState() const { return m_serializedState; }
-    const ScriptValue& state() const { return m_state; }
     History* history() const { return m_history.get(); }
 
     virtual const AtomicString& interfaceName() const;
 
+    bool isStateSet() const { return m_stateIsSet; }
+
 private:
     PopStateEvent();
     PopStateEvent(const AtomicString&, const PopStateEventInit&);
     explicit PopStateEvent(PassRefPtr<SerializedScriptValue>, PassRefPtr<History>);
 
-    ScriptValue m_state;
     RefPtr<SerializedScriptValue> m_serializedState;
     RefPtr<History> m_history;
+    bool m_stateIsSet;
 };
 
 } // namespace WebCore
 
 #endif // PopStateEvent_h