Add a basic DOMWindow base class and use it in WindowProxy.

Source/core/frame/LocalFrame.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Simon Hausmann <hausmann@kde.org>
  *                     2000 Stefan Schimanski <1Stein@gmx.de>
  *                     2001 George Staikos <staikos@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2005 Alexey Proskuryakov <ap@nypop.com>
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
@@ skipping 204 matching lines @@
 #endif
 }
 
 void LocalFrame::trace(Visitor* visitor)
 {
 #if ENABLE(OILPAN)
     visitor->trace(m_destructionObservers);
     visitor->trace(m_loader);
     visitor->trace(m_navigationScheduler);
     visitor->trace(m_view);
+    visitor->trace(m_domWindow);
     visitor->trace(m_pagePopupOwner);
     visitor->trace(m_script);
     visitor->trace(m_editor);
     visitor->trace(m_spellChecker);
     visitor->trace(m_selection);
     visitor->trace(m_eventHandler);
     visitor->trace(m_console);
     visitor->trace(m_inputMethodController);
     visitor->registerWeakMembers<LocalFrame, &LocalFrame::clearWeakMembers>(this);
     HeapSupplementable<LocalFrame>::trace(visitor);
 #endif
     Frame::trace(visitor);
 }
 
+LocalDOMWindow* LocalFrame::domWindow() const
+{
+    return m_domWindow.get();
+}
+
 void LocalFrame::navigate(Document& originDocument, const KURL& url, bool lockBackForwardList)
 {
     m_navigationScheduler.scheduleLocationChange(&originDocument, url.string(), lockBackForwardList);
 }
 
 void LocalFrame::detach()
 {
     // A lot of the following steps can result in the current frame being
     // detached, so protect a reference to it.
     RefPtrWillBeRawPtr<LocalFrame> protect(this);
@@ skipping 80 matching lines @@
     //    Frame::setDOMWindow().) The Member references it clears will now
     //    die with the window. And the registered DOMWindowProperty instances that don't,
     //    only keep a weak reference to this frame, so there's no need to be
     //    explicitly notified that this frame is going away.
     if (m_domWindow && host()) {
         host()->consoleMessageStorage().frameWindowDiscarded(m_domWindow.get());
         InspectorInstrumentation::frameWindowDiscarded(this, m_domWindow.get());
     }
     if (domWindow)
         script().clearWindowProxy();
-    Frame::setDOMWindow(domWindow);
+
+    if (m_domWindow)
+        m_domWindow->reset();
+    m_domWindow = domWindow;
 }
 
 Document* LocalFrame::document() const
 {
     return m_domWindow ? m_domWindow->document() : 0;
 }
 
 void LocalFrame::setPagePopupOwner(Element& owner)
 {
     m_pagePopupOwner = &owner;
@@ skipping 425 matching lines @@
     // We detach the FrameView's custom scroll bars as early as
     // possible to prevent m_doc->detach() from messing with the view
     // such that its scroll bars won't be torn down.
     //
     // FIXME: We should revisit this.
     if (m_view)
         m_view->prepareForDetach();
 }
 
 } // namespace blink