chrome: Cleanup class/struct forward declarations

chrome/renderer/chrome_render_view_observer.h

 // 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.
 
 #ifndef CHROME_RENDERER_CHROME_RENDER_VIEW_OBSERVER_H_
 #define CHROME_RENDERER_CHROME_RENDER_VIEW_OBSERVER_H_
 
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/timer/timer.h"
 #include "build/build_config.h"
 #include "content/public/common/browser_controls_state.h"
 #include "content/public/renderer/render_view_observer.h"
 #include "extensions/features/features.h"
 #include "url/gurl.h"
 
-class ContentSettingsObserver;
-class SkBitmap;
-
 namespace blink {
-class WebView;
 struct WebWindowFeatures;
 }
 
 namespace web_cache {
 class WebCacheImpl;
 }
 
 // This class holds the Chrome specific parts of RenderView, and has the same
 // lifetime.
 class ChromeRenderViewObserver : public content::RenderViewObserver {
@@ skipping 35 matching lines @@
   // Owned by ChromeContentRendererClient and outlive us.
   web_cache::WebCacheImpl* web_cache_impl_;
 
   // true if webview is overlayed with grey color.
   bool webview_visually_deemphasized_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeRenderViewObserver);
 };
 
 #endif  // CHROME_RENDERER_CHROME_RENDER_VIEW_OBSERVER_H_