content: Cleanup class/struct forward declarations

content/public/browser/render_frame_host.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 CONTENT_PUBLIC_BROWSER_RENDER_FRAME_HOST_H_
 #define CONTENT_PUBLIC_BROWSER_RENDER_FRAME_HOST_H_
 
 #include <string>
 
 #include "base/callback_forward.h"
@@ skipping 17 matching lines @@
 class InterfaceRegistry;
 class InterfaceProvider;
 }
 
 namespace ui {
 struct AXActionData;
 }
 
 namespace content {
 class AssociatedInterfaceProvider;
-class AssociatedInterfaceRegistry;
 class RenderProcessHost;
 class RenderViewHost;
 class RenderWidgetHostView;
 class SiteInstance;
 struct FileChooserFileInfo;
 
 // The interface provides a communication conduit with a frame in the renderer.
 class CONTENT_EXPORT RenderFrameHost : public IPC::Listener,
                                        public IPC::Sender {
  public:
@@ skipping 173 matching lines @@
 
  private:
   // This interface should only be implemented inside content.
   friend class RenderFrameHostImpl;
   RenderFrameHost() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_RENDER_FRAME_HOST_H_