Cleanup: Remove unneeded forward declarations in chrome/renderer.

chrome/renderer/extensions/chrome_v8_context.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_RENDERER_EXTENSIONS_CHROME_V8_CONTEXT_H_
 #define CHROME_RENDERER_EXTENSIONS_CHROME_V8_CONTEXT_H_
 #pragma once
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "v8/include/v8.h"
 
 namespace WebKit {
 class WebFrame;
 }
 
-namespace base {
-class ListValue;
-}
-
 namespace content {
 class RenderView;
 }
 
 // Chrome's wrapper for a v8 context.
 //
 // TODO(aa): Consider converting this back to a set of bindings_utils. It would
 // require adding WebFrame::GetIsolatedWorldIdByV8Context() to WebCore, but then
 // we won't need this object and it's a bit less state to keep track of.
 class ChromeV8Context {
@@ skipping 52 matching lines @@
   // object can outlive is destroyed asynchronously.
   WebKit::WebFrame* web_frame_;
 
   // The extension ID this context is associated with.
   std::string extension_id_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeV8Context);
 };
 
 #endif  // CHROME_RENDERER_EXTENSIONS_CHROME_V8_CONTEXT_H_