Use a direct include of the message_loop header in chromeos/.

chromeos/dbus/ibus/ibus_engine_factory_service_unittest.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 "chromeos/dbus/ibus/ibus_engine_factory_service.h"
 
 #include <map>
 #include <string>
-#include "base/message_loop.h"
+#include "base/message_loop/message_loop.h"
 #include "chromeos/dbus/ibus/ibus_constants.h"
 #include "dbus/message.h"
 #include "dbus/mock_bus.h"
 #include "dbus/mock_exported_object.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using ::testing::Invoke;
 using ::testing::Return;
 using ::testing::StrEq;
@@ skipping 203 matching lines @@
   // Unset the handler so expect not calling handler.
   service_->UnsetCreateEngineHandler(kSampleEngine);
   method_exported_map_[ibus::engine_factory::kCreateEngineMethod].Run(
       &method_call,
       base::Bind(&MockCreateEngineResponseSender::CheckCreateEngineResponse,
                  base::Unretained(&response_sender)));
   message_loop_.RunUntilIdle();
 }
 
 }  // namespace chromeos