Pass task runners to AudioManager constructor.

media/audio/sounds/audio_stream_handler_unittest.cc

Index: media/audio/sounds/audio_stream_handler_unittest.cc
diff --git a/media/audio/sounds/audio_stream_handler_unittest.cc b/media/audio/sounds/audio_stream_handler_unittest.cc
index 1b87ca424ac48794c6c59b5fbfa96d6def94d5d7..593bc62a0df3cd2dee13f3842161f0479f0097f9 100644
--- a/media/audio/sounds/audio_stream_handler_unittest.cc
+++ b/media/audio/sounds/audio_stream_handler_unittest.cc
@@ -25,7 +25,8 @@ class AudioStreamHandlerTest : public testing::Test {
   ~AudioStreamHandlerTest() override {}
 
   void SetUp() override {
-    audio_manager_.reset(AudioManager::CreateForTesting());
+    audio_manager_ =
+        AudioManager::CreateForTesting(message_loop_.task_runner());
 
     base::StringPiece data(kTestAudioData, arraysize(kTestAudioData));
     audio_stream_handler_.reset(new AudioStreamHandler(data));
@@ -33,6 +34,11 @@ class AudioStreamHandlerTest : public testing::Test {
 
   void TearDown() override {
     audio_stream_handler_.reset();
+    // AudioStreamHandler destructor posts stop and delete task to audio thread.
+    // Flush audio thread to ensure that those tasks are run before attempting
+    // to destroy AudioManager.
+    base::RunLoop().RunUntilIdle();
+
     audio_manager_.reset();
   }
 
@@ -50,7 +56,7 @@ class AudioStreamHandlerTest : public testing::Test {
   }
 
  private:
-  scoped_ptr<AudioManager> audio_manager_;
+  ScopedAudioManagerPtr audio_manager_;
   scoped_ptr<AudioStreamHandler> audio_stream_handler_;
 
   base::MessageLoop message_loop_;