Revert of Pass task runners to AudioManager constructor.

media/audio/cras/audio_manager_cras.cc

Index: media/audio/cras/audio_manager_cras.cc
diff --git a/media/audio/cras/audio_manager_cras.cc b/media/audio/cras/audio_manager_cras.cc
index 0d70a58d5faf8686179e8b81ed2a15497f6eb664..2a9b77d07cac8c8f486fa33d8e7696d9e8dd0cd2 100644
--- a/media/audio/cras/audio_manager_cras.cc
+++ b/media/audio/cras/audio_manager_cras.cc
@@ -135,13 +135,8 @@
   return false;
 }
 
-AudioManagerCras::AudioManagerCras(
-    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-    scoped_refptr<base::SingleThreadTaskRunner> worker_task_runner,
-    AudioLogFactory* audio_log_factory)
-    : AudioManagerBase(std::move(task_runner),
-                       std::move(worker_task_runner),
-                       audio_log_factory),
+AudioManagerCras::AudioManagerCras(AudioLogFactory* audio_log_factory)
+    : AudioManagerBase(audio_log_factory),
       beamforming_on_device_id_(nullptr),
       beamforming_off_device_id_(nullptr) {
   SetMaxOutputStreamsAllowed(kMaxOutputStreams);