Cleanup: Remove forward declarations in various chrome/browser directories.

chrome/browser/prerender/prerender_contents.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_CONTENTS_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_
 #pragma once
 
 #include <list>
 #include <string>
@@ skipping 12 matching lines @@
 class SessionStorageNamespace;
 class TabContents;
 class TabContentsWrapper;
 struct FaviconURL;
 struct ViewHostMsg_FrameNavigate_Params;
 
 namespace base {
 class ProcessMetrics;
 }
 
-namespace gfx {
-class Rect;
-}
-
 namespace prerender {
 
 class PrerenderManager;
 class PrerenderRenderViewHostObserver;
 class PrerenderTracker;
 
 // This class is a peer of TabContents. It can host a renderer, but does not
 // have any visible display. Its navigation is not managed by a
 // NavigationController because is has no facility for navigating (other than
 // programatically view window.location.href) or RenderViewHostManager because
@@ skipping 265 matching lines @@
 
   // Offset by which to offset prerendered pages
   static const int32 kPrerenderPageIdOffset = 10;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderContents);
 };
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_