Fix the crash that could occur when the window is closed while web contents drag is in progress.

content/browser/web_contents/web_contents_view_mac.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_WEB_CONTENTS_WEB_CONTENTS_VIEW_MAC_H_
 #define CONTENT_BROWSER_WEB_CONTENTS_WEB_CONTENTS_VIEW_MAC_H_
 
 #import <Cocoa/Cocoa.h>
 
 #include <string>
@@ skipping 60 matching lines @@
   virtual void GetContainerBounds(gfx::Rect* out) const OVERRIDE;
   virtual void RenderViewCreated(content::RenderViewHost* host) OVERRIDE;
   virtual void SetPageTitle(const string16& title) OVERRIDE;
   virtual void OnTabCrashed(base::TerminationStatus status,
                             int error_code) OVERRIDE;
   virtual void SizeContents(const gfx::Size& size) OVERRIDE;
   virtual void Focus() OVERRIDE;
   virtual void SetInitialFocus() OVERRIDE;
   virtual void StoreFocus() OVERRIDE;
   virtual void RestoreFocus() OVERRIDE;
-  virtual bool IsDoingDrag() const OVERRIDE;
-  virtual void CancelDragAndCloseTab() OVERRIDE;
   virtual WebDropData* GetDropData() const OVERRIDE;
   virtual bool IsEventTracking() const OVERRIDE;
   virtual void CloseTabAfterEventTracking() OVERRIDE;
   virtual gfx::Rect GetViewBounds() const OVERRIDE;
 
   // Backend implementation of RenderViewHostDelegateView.
   virtual void ShowContextMenu(
       const content::ContextMenuParams& params,
       content::ContextMenuSourceType type) OVERRIDE;
   virtual void ShowPopupMenu(const gfx::Rect& bounds,
@@ skipping 29 matching lines @@
   // focus returns.
   scoped_nsobject<FocusTracker> focus_tracker_;
 
   // Our optional delegate.
   scoped_ptr<content::WebContentsViewDelegate> delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(WebContentsViewMac);
 };
 
 #endif  // CONTENT_BROWSER_WEB_CONTENTS_WEB_CONTENTS_VIEW_MAC_H_