content: Cleanup class/struct forward declarations

content/public/renderer/render_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_PUBLIC_RENDERER_RENDER_VIEW_H_
 #define CONTENT_PUBLIC_RENDERER_RENDER_VIEW_H_
 
 #include <stddef.h>
 
 #include <string>
 
 #include "base/strings/string16.h"
 #include "build/build_config.h"
 #include "content/common/content_export.h"
 #include "content/public/common/browser_controls_state.h"
 #include "ipc/ipc_sender.h"
 #include "ui/gfx/geometry/rect_f.h"
 #include "ui/gfx/native_widget_types.h"
 
 namespace blink {
 class WebElement;
-class WebFrame;
 class WebFrameWidget;
 class WebView;
 struct WebRect;
 }  // namespace blink
 
 namespace gfx {
 class Size;
 }
 
 namespace content {
@@ skipping 102 matching lines @@
 
  private:
   // This interface should only be implemented inside content.
   friend class RenderViewImpl;
   RenderView() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_RENDERER_RENDER_VIEW_H_