Oilpan: add [WillBeGarbageCollected] for Node.

Source/core/frame/DOMWindow.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 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 471 matching lines @@
         enqueuePopstateEvent(stateObject);
     else
         m_pendingStateObject = stateObject;
 }
 
 DOMWindow::~DOMWindow()
 {
     ASSERT(m_hasBeenReset);
     reset();
 
+#if ENABLE(OILPAN)
+    // Stub out early to prevent Document access in removeAllEventListeners().
+    m_document = nullptr;

[haraken, 2014/05/23 12:23:27]

I'm not sure if it's OK to clear m_document here.

If the Document and the DOMWindow die together, it's OK to clear m_document
here, so that removeAllEventListeners doesn't try to
document->didClearTouchEventHandlers(document). However, if the Document
outlives the DOMWindow, we need to call
document->didClearTouchEventHandlers(document).

[sof, 2014/05/23 14:29:07]

I think we can address that via DOMWindow::clearWeakMembers() when clearing
m_domWindow when it goes out of scope. What do you think?

+#endif
+
     removeAllEventListeners();
 
 #if ENABLE(OILPAN)
-    ASSERT(m_document->isDisposed());
+    // FIXME: This should be part of ActiveDOM Object shutdown
+    clearEventQueue();
 #else
     ASSERT(m_document->isStopped());
+    clearDocument();
 #endif
-
-    clearDocument();
 }
 
 const AtomicString& DOMWindow::interfaceName() const
 {
     return EventTargetNames::DOMWindow;
 }
 
 ExecutionContext* DOMWindow::executionContext() const
 {
     return m_document.get();
@@ skipping 1357 matching lines @@
     return static_cast<DOMWindowLifecycleNotifier&>(LifecycleContext<DOMWindow>::lifecycleNotifier());
 }
 
 PassOwnPtr<LifecycleNotifier<DOMWindow> > DOMWindow::createLifecycleNotifier()
 {
     return DOMWindowLifecycleNotifier::create(this);
 }
 
 void DOMWindow::trace(Visitor* visitor)
 {
+    visitor->trace(m_document);
     visitor->trace(m_screen);
     visitor->trace(m_history);
     visitor->trace(m_locationbar);
     visitor->trace(m_menubar);
     visitor->trace(m_personalbar);
     visitor->trace(m_scrollbars);
     visitor->trace(m_statusbar);
     visitor->trace(m_toolbar);
     visitor->trace(m_console);
     visitor->trace(m_navigator);
     visitor->trace(m_location);
     visitor->trace(m_media);
     visitor->trace(m_sessionStorage);
     visitor->trace(m_localStorage);
     visitor->trace(m_applicationCache);
     visitor->trace(m_performance);
     visitor->trace(m_css);
     WillBeHeapSupplementable<DOMWindow>::trace(visitor);
 }
 
 } // namespace WebCore