Remove all event listeners during window's frame destruction step.

Source/core/frame/DOMWindowLifecycleObserver.h

 
 /*
  * Copyright (C) 2013 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 19 matching lines @@
 #include "core/frame/LocalDOMWindow.h"
 #include "platform/LifecycleObserver.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
 class DOMWindowLifecycleNotifier;
 
 class DOMWindowLifecycleObserver : public LifecycleObserver<LocalDOMWindow, DOMWindowLifecycleObserver, DOMWindowLifecycleNotifier> {
 public:
-    virtual void contextDestroyed()
-    {
-        didRemoveAllEventListeners(lifecycleContext());
-        LifecycleObserver<LocalDOMWindow, DOMWindowLifecycleObserver, DOMWindowLifecycleNotifier>::contextDestroyed();
-    }
     virtual void didAddEventListener(LocalDOMWindow*, const AtomicString&) { }
     virtual void didRemoveEventListener(LocalDOMWindow*, const AtomicString&) { }
     virtual void didRemoveAllEventListeners(LocalDOMWindow*) { }
 
 protected:
     explicit DOMWindowLifecycleObserver(LocalDOMWindow*);
     virtual ~DOMWindowLifecycleObserver();
 };
 
 } // namespace blink
 
 #endif // DOMWindowLifecycleObserver_h