move favicon download code from chrome/ into content/

chrome/browser/prerender/prerender_render_view_host_observer.h

 // Copyright (c) 2011 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_BROWSER_PRERENDER_PRERENDER_RENDER_VIEW_HOST_OBSERVER_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_RENDER_VIEW_HOST_OBSERVER_H_
 
 #include <vector>
 
 #include "content/public/browser/render_view_host_observer.h"
 
-struct FaviconURL;
 
 namespace content {
+struct FaviconURL;
 class RenderViewHost;
 }
 
 namespace IPC {
 class Message;
 }
 
 namespace prerender {
 
 class PrerenderContents;
 
 // Observer for RenderViewHost messages.
 class PrerenderRenderViewHostObserver : public content::RenderViewHostObserver {
  public:
   PrerenderRenderViewHostObserver(PrerenderContents* prerender_contents,
                                   content::RenderViewHost* render_view_host);
 
   virtual void RenderViewHostDestroyed(content::RenderViewHost* rvh) OVERRIDE;
 
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
   virtual bool Send(IPC::Message* message) OVERRIDE;
 
   void set_prerender_contents(PrerenderContents* prerender_contents) {
     prerender_contents_ = prerender_contents;
   }
 
  private:
   // Message handlers.
-  void OnUpdateFaviconURL(int32 page_id, const std::vector<FaviconURL>& urls);
+
   void OnMaybeCancelPrerenderForHTML5Media();
   void OnCancelPrerenderForPrinting();
 
   // The associated prerender contents.
   PrerenderContents* prerender_contents_;
 };
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_RENDER_VIEW_HOST_OBSERVER_H_