content: Cleanup class/struct forward declarations

content/browser/renderer_host/render_view_host_delegate_view.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 CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_VIEW_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_VIEW_H_
 
 #include <vector>
 
 #include "base/callback.h"
 #include "build/build_config.h"
 #include "content/common/content_export.h"
 #include "content/common/drag_event_source_info.h"
 #include "third_party/WebKit/public/platform/WebDragOperation.h"
 
-class SkBitmap;
-
 namespace gfx {
 class ImageSkia;
 class Rect;
 class Vector2d;
 }
 
-namespace ui {
-class GestureEvent;
-class MouseEvent;
-}
-
 namespace content {
 class RenderFrameHost;
 struct ContextMenuParams;
 struct DropData;
 struct MenuItem;
 
 // This class provides a way for the RenderViewHost to reach out to its
 // delegate's view. It only needs to be implemented by embedders if they don't
 // use the default WebContentsView implementations.
 class CONTENT_EXPORT RenderViewHostDelegateView {
@@ skipping 43 matching lines @@
   virtual void HidePopupMenu() {};
 #endif
 
  protected:
   virtual ~RenderViewHostDelegateView() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_VIEW_HOST_DELEGATE_VIEW_H_