We have a problem in the process on destroying WebContentsImpl because

content/public/test/test_navigation_observer.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 "content/public/test/test_navigation_observer.h"
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/stl_util.h"
@@ skipping 16 matching lines @@
   // WebContentsObserver:
   virtual void NavigationEntryCommitted(
       const LoadCommittedDetails& load_details) OVERRIDE {
     parent_->OnNavigationEntryCommitted(this, web_contents(), load_details);
   }
 
   virtual void DidAttachInterstitialPage() OVERRIDE {
     parent_->OnDidAttachInterstitialPage(web_contents());
   }
 
-  virtual void WebContentsDestroyed(WebContents* web_contents) OVERRIDE {
-    parent_->OnWebContentsDestroyed(this, web_contents);
+  virtual void WebContentsDestroyed() OVERRIDE {
+    parent_->OnWebContentsDestroyed(this, web_contents());
   }
 
   virtual void DidStartLoading(RenderViewHost* render_view_host) OVERRIDE {
     parent_->OnDidStartLoading(web_contents());
   }
 
   virtual void DidStopLoading(RenderViewHost* render_view_host) OVERRIDE {
     parent_->OnDidStopLoading(web_contents());
   }
 
@@ skipping 89 matching lines @@
     return;
 
   ++navigations_completed_;
   if (navigations_completed_ == number_of_navigations_) {
     navigation_started_ = false;
     message_loop_runner_->Quit();
   }
 }
 
 }  // namespace content