Oilpan: revert back to a prefinalizer for LocalDOMWindow.

Source/core/frame/LocalDOMWindow.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 252 matching lines @@
     return frame() && allowPopUp(*frame());
 }
 
 LocalDOMWindow::LocalDOMWindow(LocalFrame& frame)
     : m_frameObserver(WindowFrameObserver::create(this, frame))
     , m_shouldPrintWhenFinishedLoading(false)
 #if ENABLE(ASSERT)
     , m_hasBeenReset(false)
 #endif
 {
+#if ENABLE(OILPAN)
+    ThreadState::current()->registerPreFinalizer(*this);
+#endif
 }
 
 void LocalDOMWindow::clearDocument()
 {
     if (!m_document)
         return;
 
     ASSERT(!m_document->isActive());
 
     // FIXME: This should be part of ActiveDOMObject shutdown
@@ skipping 127 matching lines @@
         enqueuePopstateEvent(stateObject);
     else
         m_pendingStateObject = stateObject;
 }
 
 LocalDOMWindow::~LocalDOMWindow()
 {
 #if ENABLE(OILPAN)
     // Cleared when detaching document.
     ASSERT(!m_eventQueue);
-
-    // Oilpan: should the LocalDOMWindow be GCed along with its LocalFrame without the
-    // frame having first notified its observers of imminent destruction, the
-    // LocalDOMWindow will not have had an opportunity to remove event listeners.
-    //
-    // Non-Oilpan, LocalDOMWindow::reset() will always be invoked, the last opportunity
-    // being via ~LocalFrame's setDOMWindow() call. Asserted for below.
-    if (frame())
-        removeAllEventListeners();
 #else
     ASSERT(m_hasBeenReset);
     ASSERT(m_document->isStopped());
     clearDocument();
 #endif
 }
 
+void LocalDOMWindow::dispose()
+{
+    // Oilpan: should the LocalDOMWindow be GCed along with its LocalFrame without the
+    // frame having first notified its observers of imminent destruction, the
+    // LocalDOMWindow will not have had an opportunity to remove event listeners.
+    //
+    // Arrange for that removal to happen using a prefinalizer action. Making LocalDOMWindow
+    // eager finalizable is problematic as other eagerly finalized objects may well
+    // want to access their associated LocalDOMWindow from their destructors.
+    //
+    // (Non-Oilpan, LocalDOMWindow::reset() will always be invoked, the last opportunity
+    // being via ~LocalFrame's setDOMWindow() call. Asserted for in the destructor.)
+    if (!frame())
+        return;
+
+    removeAllEventListeners();
+}
+
 ExecutionContext* LocalDOMWindow::executionContext() const
 {
     return m_document.get();
 }
 
 LocalDOMWindow* LocalDOMWindow::toDOMWindow()
 {
     return this;
 }
 
@@ skipping 1067 matching lines @@
     DOMWindow::trace(visitor);
     DOMWindowLifecycleNotifier::trace(visitor);
 }
 
 LocalFrame* LocalDOMWindow::frame() const
 {
     return m_frameObserver->frame();
 }
 
 } // namespace blink