Move the frame tree into the embedder.

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 1011 matching lines @@
         (*it)->loader().detachFromParent();
 }
 
 void FrameLoader::closeAndRemoveChild(Frame* child)
 {
     child->setView(0);
     if (child->ownerElement() && child->page())
         child->page()->decrementSubframeCount();
     child->willDetachFrameHost();
     child->loader().detachClient();
-
-    m_frame->tree().removeChild(child);
 }
 
 // Called every time a resource is completely loaded or an error is received.
 void FrameLoader::checkLoadComplete()
 {
     ASSERT(m_client->hasWebView());
 
     // FIXME: Always traversing the entire frame tree is a bit inefficient, but
     // is currently needed in order to null out the previous history item for all frames.
     if (Page* page = m_frame->page()) {
@@ skipping 409 matching lines @@
 {
     SandboxFlags flags = m_forcedSandboxFlags;
     if (Frame* parentFrame = m_frame->tree().parent())
         flags |= parentFrame->document()->sandboxFlags();
     if (HTMLFrameOwnerElement* ownerElement = m_frame->ownerElement())
         flags |= ownerElement->sandboxFlags();
     return flags;
 }
 
 } // namespace WebCore