We have a problem in the process on destroying WebContentsImpl because

chrome/browser/ui/sync/one_click_signin_helper.cc

 // 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.
 
 #include "chrome/browser/ui/sync/one_click_signin_helper.h"
 
 #include <algorithm>
 #include <functional>
 #include <utility>
 #include <vector>
@@ skipping 408 matching lines @@
 // Watch a webcontents and remove URL from the history once loading is complete.
 // We have to delay the cleaning until the new URL has finished loading because
 // we're not allowed to remove the last-loaded URL from the history.  Objects
 // of this type automatically self-destruct once they're finished their work.
 class CurrentHistoryCleaner : public content::WebContentsObserver {
  public:
   explicit CurrentHistoryCleaner(content::WebContents* contents);
   virtual ~CurrentHistoryCleaner();
 
   // content::WebContentsObserver:
-  virtual void WebContentsDestroyed(content::WebContents* contents) OVERRIDE;
+  virtual void WebContentsDestroyed() OVERRIDE;
   virtual void DidCommitProvisionalLoadForFrame(
       int64 frame_id,
       const base::string16& frame_unique_name,
       bool is_main_frame,
       const GURL& url,
       content::PageTransition transition_type,
       content::RenderViewHost* render_view_host) OVERRIDE;
 
  private:
   scoped_ptr<content::WebContents> contents_;
@@ skipping 32 matching lines @@
     content::NavigationEntry* entry =
         nc->GetEntryAtIndex(history_index_to_remove_);
     if (signin::IsContinueUrlForWebBasedSigninFlow(entry->GetURL())) {
       hs->DeleteURL(entry->GetURL());
       nc->RemoveEntryAtIndex(history_index_to_remove_);
       delete this;  // Success.
     }
   }
 }
 
-void CurrentHistoryCleaner::WebContentsDestroyed(
-    content::WebContents* contents) {
+void CurrentHistoryCleaner::WebContentsDestroyed() {
   delete this;  // Failure.
 }
 
 }  // namespace
 
 
 // StartSyncArgs --------------------------------------------------------------
 
 OneClickSigninHelper::StartSyncArgs::StartSyncArgs()
     : profile(NULL),
@@ skipping 1104 matching lines @@
     // If the web contents is showing a blank page and not about to be closed,
     // redirect to the NTP or apps page.
     if (signin::IsContinueUrlForWebBasedSigninFlow(current_url) &&
         !signin::IsAutoCloseEnabledInURL(original_continue_url_)) {
       RedirectToNtpOrAppsPage(
           web_contents(),
           signin::GetSourceForPromoURL(original_continue_url_));
     }
   }
 }