Remove use of deprecated MessageLoop methods in content.

content/browser/media/session/media_session_delegate_android_browsertest.cc

 // Copyright 2016 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 <memory>
 
 #include "base/command_line.h"
+#include "base/location.h"
 #include "base/run_loop.h"
+#include "base/single_thread_task_runner.h"
+#include "base/threading/thread_task_runner_handle.h"
 #include "content/browser/media/session/media_session.h"
 #include "content/browser/media/session/mock_media_session_observer.h"
 #include "content/public/test/content_browser_test.h"
 #include "content/shell/browser/shell.h"
 
 namespace content {
 
 class MediaSessionDelegateAndroidBrowserTest : public ContentBrowserTest {};
 
 // MAYBE_OnAudioFocusChangeAfterDtorCrash will hit a DCHECK before the crash, it
@@ skipping 31 matching lines @@
                                  MediaSession::Type::Content);
   EXPECT_TRUE(media_session->IsActive());
   EXPECT_TRUE(other_media_session->IsActive());
 
   shell()->CloseAllWindows();
 
   // Give some time to the AudioFocusManager to send an audioFocusChange message
   // to the listeners. If the bug is still present, it will crash.
   {
     base::RunLoop run_loop;
-    base::MessageLoop::current()->PostDelayedTask(
+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
         FROM_HERE, run_loop.QuitClosure(), base::TimeDelta::FromSeconds(1));
     run_loop.Run();
   }
 }
 
 }  // namespace content