Remove BackForwardClient, cleanup starting a history navigation

Source/core/page/Page.h

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 22 matching lines @@
 #include "platform/geometry/Region.h"
 #include "platform/heap/Handle.h"
 #include "wtf/Forward.h"
 #include "wtf/HashSet.h"
 #include "wtf/Noncopyable.h"
 #include "wtf/text/WTFString.h"
 
 namespace blink {
 
 class AutoscrollController;
-class BackForwardClient;
 class Chrome;
 class ChromeClient;
 class ClientRectList;
 class ContextMenuClient;
 class ContextMenuController;
 class Document;
 class DragCaretController;
 class DragClient;
 class DragController;
 class EditorClient;
@@ skipping 29 matching lines @@
         WTF_MAKE_NONCOPYABLE(PageClients); WTF_MAKE_FAST_ALLOCATED;
     public:
         PageClients();
         ~PageClients();
 
         ChromeClient* chromeClient;
         ContextMenuClient* contextMenuClient;
         EditorClient* editorClient;
         DragClient* dragClient;
         InspectorClient* inspectorClient;
-        BackForwardClient* backForwardClient;
         SpellCheckerClient* spellCheckerClient;
         StorageClient* storageClient;
     };
 
     explicit Page(PageClients&);
     virtual ~Page();
 
     void makeOrdinary();
 
     // This method returns all pages, incl. private ones associated with
@@ skipping 41 matching lines @@
     PointerLockController& pointerLockController() const { return *m_pointerLockController; }
     ValidationMessageClient& validationMessageClient() const { return *m_validationMessageClient; }
     void setValidationMessageClient(PassOwnPtrWillBeRawPtr<ValidationMessageClient>);
 
     ScrollingCoordinator* scrollingCoordinator();
 
     String mainThreadScrollingReasonsAsText();
     PassRefPtrWillBeRawPtr<ClientRectList> nonFastScrollableRects(const LocalFrame*);
 
     Settings& settings() const { return *m_settings; }
-    BackForwardClient& backForward() const { return *m_backForwardClient; }
 
     UseCounter& useCounter() { return m_useCounter; }
 
     void setTabKeyCyclesThroughElements(bool b) { m_tabKeyCyclesThroughElements = b; }
     bool tabKeyCyclesThroughElements() const { return m_tabKeyCyclesThroughElements; }
 
     void unmarkAllTextMatches();
 
     // DefersLoading is used to delay loads during modal dialogs.
     // Modal dialogs are supposed to freeze all background processes
@@ skipping 80 matching lines @@
     // WebPagePopupImpl) which don't hold a reference to the main frame at all
     // after creating it. These are still safe because they always create a
     // Frame with a FrameView. FrameView and Frame hold references to each
     // other, thus keeping each other alive. The call to willBeDestroyed()
     // breaks this cycle, so the frame is still properly destroyed once no
     // longer needed.
     RawPtrWillBeMember<Frame> m_mainFrame;
 
     mutable RefPtr<PluginData> m_pluginData;
 
-    BackForwardClient* m_backForwardClient;
     EditorClient* const m_editorClient;
     SpellCheckerClient* const m_spellCheckerClient;
     StorageClient* m_storageClient;
     OwnPtrWillBeMember<ValidationMessageClient> m_validationMessageClient;
 
     UseCounter m_useCounter;
 
     bool m_openedByDOM;
 
     bool m_tabKeyCyclesThroughElements;
@@ skipping 16 matching lines @@
     WillBeHeapHashSet<RawPtrWillBeWeakMember<MultisamplingChangedObserver> > m_multisamplingChangedObservers;
 
     // A pointer to all the interfaces provided to in-process Frames for this Page.
     // FIXME: Most of the members of Page should move onto FrameHost.
     OwnPtrWillBeMember<FrameHost> m_frameHost;
 };
 
 } // namespace blink
 
 #endif // Page_h