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

chrome/browser/extensions/message_handler.cc

 // 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.
 
 #include "chrome/browser/extensions/message_handler.h"
 
+#include "base/values.h"
 #include "chrome/browser/extensions/api/messaging/message_service.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/extensions/extension_messages.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 #include "extensions/browser/view_type_utils.h"
 
 using content::WebContents;
@@ skipping 19 matching lines @@
 }
 
 void MessageHandler::RenderViewHostInitialized() {
   WebContents* web_contents =
       WebContents::FromRenderViewHost(render_view_host());
   Send(new ExtensionMsg_NotifyRenderViewType(
       routing_id(), extensions::GetViewType(web_contents)));
 }
 
 void MessageHandler::OnPostMessage(int port_id,
-                                            const std::string& message) {
+                                   const base::ListValue& message) {
   Profile* profile = Profile::FromBrowserContext(
       render_view_host()->GetProcess()->GetBrowserContext());
   MessageService* message_service = MessageService::Get(profile);
   if (message_service) {
-    message_service->PostMessage(port_id, message);
+    message_service->PostMessage(port_id, make_scoped_ptr(message.DeepCopy()));
   }
 }
 
 }  // namespace extensions