Clean up media header include guards

media/base/fake_single_thread_task_runner.h

 // Copyright 2014 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.
 
-#ifndef MEDIA_CAST_TEST_FAKE_TASK_RUNNER_H_
-#define MEDIA_CAST_TEST_FAKE_TASK_RUNNER_H_
+#ifndef MEDIA_BASE_FAKE_SINGLE_THREAD_TASK_RUNNER_H_
+#define MEDIA_BASE_FAKE_SINGLE_THREAD_TASK_RUNNER_H_
 
 #include <map>
 
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/single_thread_task_runner.h"
 #include "base/test/simple_test_tick_clock.h"
 
 namespace media {
 
@@ skipping 34 matching lines @@
   // std::priority_queue.  http://crbug.com/530842
   std::map<TaskKey, base::Closure> tasks_;
 
   bool fail_on_next_task_;
 
   DISALLOW_COPY_AND_ASSIGN(FakeSingleThreadTaskRunner);
 };
 
 }  // namespace media
 
-#endif  // MEDIA_CAST_TEST_FAKE_TASK_RUNNER_H_
+#endif  // MEDIA_BASE_FAKE_SINGLE_THREAD_TASK_RUNNER_H_