Forward declare v8::Extension in chrome/renderer/extensions/*.

chrome/renderer/extensions/renderer_extension_bindings.cc

 // 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.
 
 #include "chrome/renderer/extensions/renderer_extension_bindings.h"
 
 #include <map>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/lazy_instance.h"
 #include "chrome/common/extensions/extension_message_bundle.h"
 #include "chrome/common/extensions/extension_messages.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/renderer/extensions/event_bindings.h"
 #include "chrome/renderer/extensions/extension_base.h"
 #include "chrome/renderer/extensions/extension_renderer_context.h"
 #include "content/renderer/render_thread.h"
 #include "content/renderer/render_view.h"
 #include "grit/renderer_resources.h"
+#include "v8/include/v8.h"
 
 // Message passing API example (in a content script):
 // var extension =
 //    new chrome.Extension('00123456789abcdef0123456789abcdef0123456');
 // var port = extension.connect();
 // port.postMessage('Can you hear me now?');
 // port.onmessage.addListener(function(msg, port) {
 //   alert('response=' + msg);
 //   port.postMessage('I got your reponse');
 // });
@@ skipping 214 matching lines @@
 }  // namespace
 
 const char* RendererExtensionBindings::kName =
     "chrome/RendererExtensionBindings";
 
 v8::Extension* RendererExtensionBindings::Get(
     ExtensionRendererContext* context) {
   static v8::Extension* extension = new ExtensionImpl(context);
   return extension;
 }