We have a problem in the process on destroying WebContentsImpl because

chrome/browser/prerender/prerender_manager.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 CHROME_BROWSER_PRERENDER_PRERENDER_MANAGER_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_MANAGER_H_
 
 #include <list>
 #include <map>
 #include <string>
@@ skipping 459 matching lines @@
         content::PageTransition transition_type,
         content::RenderViewHost* render_view_host) OVERRIDE;
     virtual void DidFailProvisionalLoad(
         int64 frame_id,
         const base::string16& frame_unique_name,
         bool is_main_frame,
         const GURL& validated_url,
         int error_code,
         const base::string16& error_description,
         content::RenderViewHost* render_view_host) OVERRIDE;
-    virtual void WebContentsDestroyed(content::WebContents* web_contents)
-        OVERRIDE;
+    virtual void WebContentsDestroyed() OVERRIDE;
 
    private:
     void RecordEvent(PrerenderEvent event) const;
 
     void OnMergeCompleted(content::SessionStorageNamespace::MergeResult result);
     void OnMergeTimeout();
 
     // Prerender parameters.
     PrerenderManager* manager_;
     PrerenderData* prerender_data_;
@@ skipping 227 matching lines @@
 
   // The value of profile_network_bytes_ that was last recorded.
   int64 last_recorded_profile_network_bytes_;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderManager);
 };
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_MANAGER_H_