Remove leak of objects between isolated worlds on custom events.

Source/core/dom/CustomEvent.h

 /*
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  *
  * 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
@@ skipping 17 matching lines @@
 
 #include "bindings/v8/ScriptValue.h"
 #include "bindings/v8/SerializedScriptValue.h"
 #include "core/dom/Event.h"
 
 namespace WebCore {
 
 struct CustomEventInit : public EventInit {
     CustomEventInit();
 
-    ScriptValue detail;
+    bool detailIsSet;
 };
 
 class CustomEvent : public Event {
 public:
     virtual ~CustomEvent();
 
     static PassRefPtr<CustomEvent> create()
     {
         return adoptRef(new CustomEvent);
     }
 
     static PassRefPtr<CustomEvent> create(const AtomicString& type, const CustomEventInit& initializer)
     {
         return adoptRef(new CustomEvent(type, initializer));
     }
 
-    void initCustomEvent(const AtomicString& type, bool canBubble, bool cancelable, const ScriptValue& detail);
     void initCustomEvent(const AtomicString& type, bool canBubble, bool cancelable, PassRefPtr<SerializedScriptValue>);
 
     virtual const AtomicString& interfaceName() const;
 
-    const ScriptValue& detail() const { return m_detail; }
     PassRefPtr<SerializedScriptValue> serializedScriptValue() { return m_serializedScriptValue; }
 
+    bool isDetailSet() const { return m_detailIsSet; }
+
 private:
     CustomEvent();
     CustomEvent(const AtomicString& type, const CustomEventInit& initializer);
 
-    ScriptValue m_detail;
     RefPtr<SerializedScriptValue> m_serializedScriptValue;
+
+    bool m_detailIsSet;
 };
 
 } // namespace WebCore
 
 #endif // CustomEvent_h