Revert of Streamline frame detach

Source/core/frame/Frame.h

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999-2001 Lars Knoll <knoll@kde.org>
  *                     1999-2001 Antti Koivisto <koivisto@kde.org>
  *                     2000-2001 Simon Hausmann <hausmann@kde.org>
  *                     2000-2001 Dirk Mueller <mueller@kde.org>
  *                     2000 Stefan Schimanski <1Stein@gmx.de>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
@@ skipping 41 matching lines @@
 
 class Frame : public RefCountedWillBeGarbageCollectedFinalized<Frame> {
 public:
     virtual bool isLocalFrame() const { return false; }
     virtual bool isRemoteFrame() const { return false; }
 
     virtual ~Frame();
     virtual void trace(Visitor*);
 
     virtual void navigate(Document& originDocument, const KURL&, const Referrer&, bool lockBackForwardList) = 0;
-    virtual void detach();
+    virtual void detach() = 0;
     void detachChildren();
 
     FrameClient* client() const;
+    void clearClient();
 
     // NOTE: Page is moving out of Blink up into the browser process as
     // part of the site-isolation (out of process iframes) work.
     // FrameHost should be used instead where possible.
     Page* page() const;
     FrameHost* host() const; // Null when the frame is detached.
 
     bool isMainFrame() const;
     bool isLocalRoot() const;
 
@@ skipping 37 matching lines @@
 private:
     FrameClient* m_client;
     WebLayer* m_remotePlatformLayer;
 };
 
 inline FrameClient* Frame::client() const
 {
     return m_client;
 }
 
+inline void Frame::clearClient()
+{
+    m_client = 0;
+}
+
 inline LocalDOMWindow* Frame::domWindow() const
 {
     return m_domWindow.get();
 }
 
 inline FrameOwner* Frame::owner() const
 {
     return m_owner;
 }
 
 inline FrameTree& Frame::tree() const
 {
     return m_treeNode;
 }
 
 // Allow equality comparisons of Frames by reference or pointer, interchangeably.
 DEFINE_COMPARISON_OPERATORS_WITH_REFERENCES_REFCOUNTED(Frame)
 
 } // namespace blink
 
 #endif // Frame_h