chrome: Cleanup class/struct forward declarations

chrome/renderer/chrome_render_frame_observer.h

 // 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.
 
 #ifndef CHROME_RENDERER_CHROME_RENDER_FRAME_OBSERVER_H_
 #define CHROME_RENDERER_CHROME_RENDER_FRAME_OBSERVER_H_
 
 #include "base/macros.h"
 #include "base/timer/timer.h"
 #include "chrome/common/prerender_types.h"
 #include "content/public/renderer/render_frame_observer.h"
 
-class GURL;
-
 namespace gfx {
 class Size;
 }
 
 namespace safe_browsing {
 class PhishingClassifierDelegate;
 }
 
 namespace translate {
 class TranslateHelper;
@@ skipping 39 matching lines @@
                             base::TimeDelta delay);
 
   // Have the same lifetime as us.
   translate::TranslateHelper* translate_helper_;
   safe_browsing::PhishingClassifierDelegate* phishing_classifier_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeRenderFrameObserver);
 };
 
 #endif  // CHROME_RENDERER_CHROME_RENDER_FRAME_OBSERVER_H_