Add a new GetInstance() method for singleton classes, take 2.

chrome/test/webdriver/commands/create_session.cc

 // Copyright (c) 2010 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/test/webdriver/commands/create_session.h"
 
 #include <sstream>
 #include <string>
 
 #include "base/values.h"
 #include "chrome/app/chrome_command_ids.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/common/chrome_switches.h"
 
 namespace webdriver {
 
 void CreateSession::ExecutePost(Response* const response) {
-  SessionManager* session_manager = Singleton<SessionManager>::get();
+  SessionManager* session_manager = SessionManager::GetInstance();
   std::string session_id;
 
   if (!session_manager->Create(&session_id)) {
     response->set_status(kUnknownError);
     response->set_value(Value::CreateStringValue("Failed to create session"));
     return;
   }
 
   VLOG(1) << "Created session " << session_id;
   std::ostringstream stream;
   stream << "http://" << session_manager->GetIPAddress() << "/session/"
          << session_id;
   response->set_status(kSeeOther);
   response->set_value(Value::CreateStringValue(stream.str()));
 }
 
 }  // namespace webdriver