We have a problem in the process on destroying WebContentsImpl because

chrome/browser/guest_view/web_view/web_view_guest.h

 // Copyright 2014 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 CHROME_BROWSER_GUEST_VIEW_WEB_VIEW_WEB_VIEW_GUEST_H_
 #define CHROME_BROWSER_GUEST_VIEW_WEB_VIEW_WEB_VIEW_GUEST_H_
 
 #include "base/observer_list.h"
 #include "chrome/browser/extensions/tab_helper.h"
 #include "chrome/browser/guest_view/guest_view.h"
@@ skipping 218 matching lines @@
       bool is_main_frame,
       const GURL& validated_url,
       bool is_error_page,
       bool is_iframe_srcdoc,
       content::RenderViewHost* render_view_host) OVERRIDE;
   virtual void DocumentLoadedInFrame(
       int64 frame_id,
       content::RenderViewHost* render_view_host) OVERRIDE;
   virtual void DidStopLoading(
       content::RenderViewHost* render_view_host) OVERRIDE;
-  virtual void WebContentsDestroyed(
-      content::WebContents* web_contents) OVERRIDE;
+  virtual void WebContentsDestroyed() OVERRIDE;
   virtual void UserAgentOverrideSet(const std::string& user_agent) OVERRIDE;
 
   // Called after the load handler is called in the guest's main frame.
   void LoadHandlerCalled();
 
   // Called when a redirect notification occurs.
   void LoadRedirect(const GURL& old_url,
                     const GURL& new_url,
                     bool is_top_level);
 
@@ skipping 63 matching lines @@
   scoped_ptr<chromeos::AccessibilityStatusSubscription>
       accessibility_subscription_;
 #endif
 
   std::map<int, int> bridge_id_to_request_id_map_;
 
   DISALLOW_COPY_AND_ASSIGN(WebViewGuest);
 };
 
 #endif  // CHROME_BROWSER_GUEST_VIEW_WEB_VIEW_WEB_VIEW_GUEST_H_