Add missing IWYU message_loop.h includes.

chrome/common/service_process_util_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 "chrome/common/service_process_util.h"
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/location.h"
+#include "base/message_loop/message_loop.h"
 #include "base/process/kill.h"
 #include "base/process/launch.h"
 #include "base/run_loop.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_split.h"
 #include "base/threading/platform_thread.h"
 #include "build/build_config.h"
 
 #if !defined(OS_MACOSX)
 #include "base/at_exit.h"
@@ skipping 219 matching lines @@
   message_loop.task_runner()->PostDelayedTask(
       FROM_HERE, run_loop.QuitWhenIdleClosure(),
       TestTimeouts::action_max_timeout());
   EXPECT_FALSE(g_good_shutdown);
   run_loop.Run();
   EXPECT_TRUE(g_good_shutdown);
   return 0;
 }
 
 #endif  // !OS_MACOSX