Move c/r/extensions/* into extensions namespace

chrome/renderer/extensions/chrome_v8_extension_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/renderer/extensions/chrome_v8_extension_handler.h"
 
 #include "base/logging.h"
 #include "chrome/renderer/extensions/chrome_v8_context.h"
 #include "content/public/renderer/render_thread.h"
 
 using content::RenderThread;
 
+namespace extensions {
+
 ChromeV8ExtensionHandler::ChromeV8ExtensionHandler(ChromeV8Context* context)
     : context_(context), routing_id_(MSG_ROUTING_NONE) {
 }
 
 ChromeV8ExtensionHandler::~ChromeV8ExtensionHandler() {
   if (routing_id_ != MSG_ROUTING_NONE)
     RenderThread::Get()->RemoveRoute(routing_id_);
 }
 
 int ChromeV8ExtensionHandler::GetRoutingID() {
   if (routing_id_ == MSG_ROUTING_NONE) {
     routing_id_ = RenderThread::Get()->GenerateRoutingID();
     RenderThread::Get()->AddRoute(routing_id_, this);
   }
 
   return routing_id_;
 }
 
 void ChromeV8ExtensionHandler::Send(IPC::Message* message) {
   RenderThread::Get()->Send(message);
 }
+
+}  // namespace extensions