We have a problem in the process on destroying WebContentsImpl because

chrome/browser/task_manager/web_contents_resource_provider.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/task_manager/web_contents_resource_provider.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/prerender/prerender_manager.h"
@@ skipping 33 matching lines @@
 
   virtual void RenderViewReady() OVERRIDE {
     provider_->RemoveFromTaskManager(web_contents());
     provider_->AddToTaskManager(web_contents());
   }
 
   virtual void RenderProcessGone(base::TerminationStatus status) OVERRIDE {
     provider_->RemoveFromTaskManager(web_contents());
   }
 
-  virtual void WebContentsDestroyed(WebContents* web_contents) OVERRIDE {
-    provider_->RemoveFromTaskManager(web_contents);
+  virtual void WebContentsDestroyed() OVERRIDE {
+    provider_->RemoveFromTaskManager(web_contents());
     provider_->DeleteObserver(this);  // Deletes |this|.
   }
 
  private:
   WebContentsResourceProvider* provider_;
 };
 
 ////////////////////////////////////////////////////////////////////////////////
 // WebContentsResourceProvider class
 ////////////////////////////////////////////////////////////////////////////////
@@ skipping 120 matching lines @@
 void WebContentsResourceProvider::DeleteObserver(
     TaskManagerWebContentsObserver* observer) {
   if (!web_contents_observers_.erase(observer)) {
     NOTREACHED();
     return;
   }
   delete observer;  // Typically, this is our caller. Deletion is okay.
 }
 
 }  // namespace task_manager