Reland 153623004: Remove the unified IO code on the browser

media/audio/alsa/audio_manager_alsa.cc

Index: media/audio/alsa/audio_manager_alsa.cc
diff --git a/media/audio/alsa/audio_manager_alsa.cc b/media/audio/alsa/audio_manager_alsa.cc
index ac61a5fa97499d3dab14ea64557877fe76a68b83..7d6421f2cfec691a7f6a7b81a221d3c7f6460347 100644
--- a/media/audio/alsa/audio_manager_alsa.cc
+++ b/media/audio/alsa/audio_manager_alsa.cc
@@ -283,11 +283,9 @@ AudioOutputStream* AudioManagerAlsa::MakeLinearOutputStream(
 
 AudioOutputStream* AudioManagerAlsa::MakeLowLatencyOutputStream(
     const AudioParameters& params,
-    const std::string& device_id,
-    const std::string& input_device_id) {
+    const std::string& device_id) {
   DLOG_IF(ERROR, !device_id.empty()) << "Not implemented!";
   DCHECK_EQ(AudioParameters::AUDIO_PCM_LOW_LATENCY, params.format());
-  // TODO(xians): Use input_device_id for unified IO.
   return MakeOutputStream(params);
 }