Use ChildFrameDisconnector when detaching child frames of a LocalFrame.

third_party/WebKit/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 63 matching lines @@
     virtual DOMWindow* domWindow() const = 0;
     virtual WindowProxy* windowProxy(DOMWrapperWorld&) = 0;
 
     virtual void navigate(Document& originDocument, const KURL&, bool replaceCurrentItem, UserGestureStatus) = 0;
     // This version of Frame::navigate assumes the resulting navigation is not
     // to be started on a timer. Use the method above in such cases.
     virtual void navigate(const FrameLoadRequest&) = 0;
     virtual void reload(FrameLoadType, ClientRedirectPolicy) = 0;
 
     virtual void detach(FrameDetachType);
-    void detachChildren();
     void disconnectOwnerElement();
     virtual bool shouldClose() = 0;
 
     FrameClient* client() const;
 
     // 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.
@@ skipping 70 matching lines @@
 {
     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