Log audio system used to WebRTC log.

media/audio/pulse/audio_manager_pulse.cc

Index: media/audio/pulse/audio_manager_pulse.cc
diff --git a/media/audio/pulse/audio_manager_pulse.cc b/media/audio/pulse/audio_manager_pulse.cc
index afa70640d4d367a11ce4afa425f8dc221a435984..779bf92e58d3d39c981f398cf911ed504bc2191f 100644
--- a/media/audio/pulse/audio_manager_pulse.cc
+++ b/media/audio/pulse/audio_manager_pulse.cc
@@ -143,6 +143,10 @@ AudioParameters AudioManagerPulse::GetInputStreamParameters(
                          buffer_size);
 }
 
+const char* AudioManagerPulse::GetName() {
+  return "PulseAudio";
+}
+
 AudioOutputStream* AudioManagerPulse::MakeLinearOutputStream(
     const AudioParameters& params,
     const LogCallback& log_callback) {