Change Page::m_mainFrame to be a Frame.

Source/core/loader/FrameLoader.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008 Alp Toker <alp@atoker.com>
  * Copyright (C) Research In Motion Limited 2009. All rights reserved.
  * Copyright (C) 2011 Kris Jordan <krisjordan@gmail.com>
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ skipping 1059 matching lines @@
     }
     FrameVector::iterator end = childrenToDetach.end();
     for (FrameVector::iterator it = childrenToDetach.begin(); it != end; ++it)
         (*it)->loader().detachFromParent();
 }
 
 // Called every time a resource is completely loaded or an error is received.
 void FrameLoader::checkLoadComplete()
 {
     ASSERT(client()->hasWebView());
-    if (Page* page = m_frame->page())
-        page->mainFrame()->loader().checkLoadCompleteForThisFrame();
+    if (Page* page = m_frame->page()) {
+        if (page->mainFrame()->isLocalFrame())
+            page->deprecatedLocalMainFrame()->loader().checkLoadCompleteForThisFrame();
+    }
 }
 
 String FrameLoader::userAgent(const KURL& url) const
 {
     String userAgent = client()->userAgent(url);
     InspectorInstrumentation::applyUserAgentOverride(m_frame, &userAgent);
     return userAgent;
 }
 
 void FrameLoader::frameDetached()
@@ skipping 380 matching lines @@
     // FIXME: We need a way to propagate sandbox flags to out-of-process frames.
     Frame* parentFrame = m_frame->tree().parent();
     if (parentFrame && parentFrame->isLocalFrame())
         flags |= toLocalFrame(parentFrame)->document()->sandboxFlags();
     if (FrameOwner* frameOwner = m_frame->owner())
         flags |= frameOwner->sandboxFlags();
     return flags;
 }
 
 } // namespace WebCore