Reland: Window.postMessage() to self can cause document leaks

Source/core/frame/LocalDOMWindow.h

 /*
  * Copyright (C) 2006, 2007, 2009, 2010 Apple Inc. All rights reserved.
  * 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
@@ skipping 150 matching lines @@
     Element* frameElement() const;
 
     PassRefPtrWillBeRawPtr<DOMWindow> open(const String& urlString, const AtomicString& frameName, const String& windowFeaturesString,
         LocalDOMWindow* callingWindow, LocalDOMWindow* enteredWindow);
 
     FrameConsole* frameConsole() const;
 
     void printErrorMessage(const String&);
 
     void postMessageTimerFired(PostMessageTimer*);
+    void removePostMessageTimer(PostMessageTimer*);
     void dispatchMessageEventWithOriginCheck(SecurityOrigin* intendedTargetOrigin, PassRefPtrWillBeRawPtr<Event>, PassRefPtrWillBeRawPtr<ScriptCallStack>);
 
     // Events
     // EventTarget API
     virtual bool addEventListener(const AtomicString& eventType, PassRefPtr<EventListener>, bool useCapture = false) override;
     virtual bool removeEventListener(const AtomicString& eventType, PassRefPtr<EventListener>, bool useCapture = false) override;
     virtual void removeAllEventListeners() override;
 
     using EventTarget::dispatchEvent;
     bool dispatchEvent(PassRefPtrWillBeRawPtr<Event> prpEvent, PassRefPtrWillBeRawPtr<EventTarget> prpTarget);
@@ skipping 103 matching lines @@
 }
 
 inline String LocalDOMWindow::defaultStatus() const
 {
     return m_defaultStatus;
 }
 
 } // namespace blink
 
 #endif // LocalDOMWindow_h