Cleanup: Remove unneeded forward declarations in chrome/renderer.

chrome/renderer/extensions/app_bindings.h

 // Copyright (c) 2011 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.
 
 // The AppObjectExtension is a v8 extension that creates an object
 // at window.chrome.app.  This object allows javascript to get details
 // on the app state of the page.
 // The read-only property app.isInstalled is true if the current page is
 // within the extent of an installed, enabled app.
 
 #ifndef CHROME_RENDERER_EXTENSIONS_APP_BINDINGS_H_
 #define CHROME_RENDERER_EXTENSIONS_APP_BINDINGS_H_
 #pragma once
 
 #include "base/compiler_specific.h"
 #include "chrome/renderer/extensions/chrome_v8_extension.h"
 
 class ChromeV8Context;
 
-namespace WebKit {
-class WebFrame;
-}
-
 // Implements the chrome.app JavaScript object.
 //
 // TODO(aa): Add unit testing for this class.
 class AppBindings : public ChromeV8Extension {
  public:
   explicit AppBindings(ExtensionDispatcher* dispatcher);
 
  protected:
   virtual ChromeV8ExtensionHandler* CreateHandler(
       ChromeV8Context* context) OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AppBindings);
 };
 
 #endif  // CHROME_RENDERER_EXTENSIONS_APP_BINDINGS_H_