We have a problem in the process on destroying WebContentsImpl because

chrome/browser/ui/sync/one_click_signin_sync_observer.cc

 // 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.
 
 #include "chrome/browser/ui/sync/one_click_signin_sync_observer.h"
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/signin/signin_promo.h"
@@ skipping 33 matching lines @@
     // before this task has a chance to run.
     base::MessageLoop::current()->PostTask(
         FROM_HERE,
         base::Bind(&OneClickSigninSyncObserver::DeleteObserver,
                    weak_ptr_factory_.GetWeakPtr()));
   }
 }
 
 OneClickSigninSyncObserver::~OneClickSigninSyncObserver() {}
 
-void OneClickSigninSyncObserver::WebContentsDestroyed(
-    content::WebContents* web_contents) {
-  ProfileSyncService* sync_service = GetSyncService(web_contents);
+void OneClickSigninSyncObserver::WebContentsDestroyed() {
+  ProfileSyncService* sync_service = GetSyncService(web_contents());
   if (sync_service)
     sync_service->RemoveObserver(this);
 
   delete this;
 }
 
 void OneClickSigninSyncObserver::OnStateChanged() {
   ProfileSyncService* sync_service = GetSyncService(web_contents());
 
   // At this point, the sign-in process is complete, and control has been handed
@@ skipping 43 matching lines @@
       Profile::FromBrowserContext(web_contents->GetBrowserContext());
   return ProfileSyncServiceFactory::GetForProfile(profile);
 }
 
 // static
 void OneClickSigninSyncObserver::DeleteObserver(
     base::WeakPtr<OneClickSigninSyncObserver> observer) {
   if (observer)
     delete observer.get();
 }