We have a problem in the process on destroying WebContentsImpl because

chrome/browser/printing/print_dialog_cloud.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/printing/print_dialog_cloud.h"
 
 
 #include "base/base64.h"
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 133 matching lines @@
       const content::LoadCommittedDetails& details,
       const content::FrameNavigateParams& params) OVERRIDE {
     if (IsSimilarUrl(params.url, cloud_print_url_)) {
       base::MessageLoop::current()->PostTask(
           FROM_HERE,
           base::Bind(&SignInObserver::OnSignIn,
                      weak_ptr_factory_.GetWeakPtr()));
     }
   }
 
-  virtual void WebContentsDestroyed(WebContents* web_contents) OVERRIDE {
+  virtual void WebContentsDestroyed() OVERRIDE {
     delete this;
   }
 
   void OnSignIn() {
     callback_.Run();
     if (web_contents())
       web_contents()->Close();
   }
 
   GURL cloud_print_url_;
@@ skipping 596 matching lines @@
 
       print_dialog_cloud::CreatePrintDialogForFile(profile, NULL,
           cloud_print_file, print_job_title, print_job_print_ticket, file_type);
       return true;
     }
   }
   return false;
 }
 
 }  // namespace print_dialog_cloud