Replace JSON (de)serialization of extension messages with direct Value pickling.

chrome/renderer/extensions/extension_helper.h

 // Copyright (c) 2012 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_EXTENSION_HELPER_H_
 #define CHROME_RENDERER_EXTENSIONS_EXTENSION_HELPER_H_
 
 #include <map>
 #include <vector>
 
@@ skipping 62 matching lines @@
   void OnExtensionMessageInvoke(const std::string& extension_id,
                                 const std::string& function_name,
                                 const base::ListValue& args,
                                 bool user_gesture);
   void OnExtensionDispatchOnConnect(
       int target_port_id,
       const std::string& channel_name,
       const base::DictionaryValue& source_tab,
       const ExtensionMsg_ExternalConnectionInfo& info);
   void OnExtensionDeliverMessage(int target_port_id,
-                                 const std::string& message);
+                                 const base::ListValue& message);
   void OnExtensionDispatchOnDisconnect(int port_id,
                                        const std::string& error_message);
   void OnExecuteCode(const ExtensionMsg_ExecuteCode_Params& params);
   void OnGetApplicationInfo(int page_id);
   void OnNotifyRendererViewType(ViewType view_type);
   void OnSetTabId(int tab_id);
   void OnUpdateBrowserWindowId(int window_id);
   void OnAddMessageToConsole(content::ConsoleMessageLevel level,
                              const std::string& message);
   void OnAppWindowClosed();
@@ skipping 17 matching lines @@
 
   // Id number of browser window which RenderView is attached to.
   int browser_window_id_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionHelper);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_RENDERER_EXTENSIONS_EXTENSION_HELPER_H_