We have a problem in the process on destroying WebContentsImpl because

chrome/browser/ui/ash/launcher/chrome_launcher_controller_unittest.cc

 // Copyright 2013 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/ash/launcher/chrome_launcher_controller.h"
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
@@ skipping 665 matching lines @@
   }
   virtual ~WebContentsDestroyedWatcher() {}
 
   // Waits until the WebContents is destroyed.
   void Wait() {
     message_loop_runner_->Run();
   }
 
  private:
   // Overridden WebContentsObserver methods.
-  virtual void WebContentsDestroyed(
-      content::WebContents* web_contents) OVERRIDE {
+  virtual void WebContentsDestroyed() OVERRIDE {
     message_loop_runner_->Quit();
   }
 
   scoped_refptr<content::MessageLoopRunner> message_loop_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(WebContentsDestroyedWatcher);
 };
 
 // A V1 windowed application.
 class V1App : public TestBrowserWindow {
@@ skipping 2001 matching lines @@
 
   EXPECT_EQ(1, app_icon_loader->fetch_count());
   ASSERT_EQ(initial_size + 1, model_->items().size());
   EXPECT_TRUE(launcher_controller_->IsAppPinned("1"));
   EXPECT_FALSE(launcher_controller_->IsAppPinned("0"));
   EXPECT_EQ(ash::TYPE_APP_SHORTCUT, model_->items()[app_index].type);
 
   launcher_controller_->UnpinAppWithID("1");
   ASSERT_EQ(initial_size, model_->items().size());
 }