Revert of Pass task runners to AudioManager constructor.

components/audio_modem/audio_player_impl.cc

 // Copyright 2015 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 "components/audio_modem/audio_player_impl.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/bind.h"
-#include "base/location.h"
+#include "base/bind_helpers.h"
 #include "base/logging.h"
+#include "base/run_loop.h"
 #include "components/audio_modem/public/audio_modem_types.h"
+#include "content/public/browser/browser_thread.h"
 #include "media/audio/audio_manager.h"
 #include "media/audio/audio_parameters.h"
 #include "media/base/audio_bus.h"
 
 namespace {
 
 const int kDefaultFrameCount = 1024;
 const double kOutputVolumePercent = 1.0f;
 
 }  // namespace
@@ skipping 129 matching lines @@
 }
 
 void AudioPlayerImpl::OnError(media::AudioOutputStream* /* stream */) {
   LOG(ERROR) << "Error during system sound reproduction.";
   media::AudioManager::Get()->GetTaskRunner()->PostTask(
       FROM_HERE,
       base::Bind(&AudioPlayerImpl::StopAndCloseOnAudioThread,
                  base::Unretained(this)));
 }
 
+void AudioPlayerImpl::FlushAudioLoopForTesting() {
+  if (media::AudioManager::Get()->GetTaskRunner()->BelongsToCurrentThread())
+    return;
+
+  // Queue task on the audio thread, when it is executed, that means we've
+  // successfully executed all the tasks before us.
+  base::RunLoop rl;
+  media::AudioManager::Get()->GetTaskRunner()->PostTaskAndReply(
+      FROM_HERE,
+      base::Bind(base::IgnoreResult(&AudioPlayerImpl::FlushAudioLoopForTesting),
+                 base::Unretained(this)),
+      rl.QuitClosure());
+  rl.Run();
+}
+
 }  // namespace audio_modem