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..8fd859a7f9b57663ef6b6e5d0fdafe1b15ec525d 100644
--- a/media/audio/pulse/audio_manager_pulse.cc
+++ b/media/audio/pulse/audio_manager_pulse.cc
@@ -48,6 +48,10 @@ static const base::FilePath::CharType kPulseLib[] =
     FILE_PATH_LITERAL("libpulse.so.0");
 #endif
 
+namespace {
+const char kAudioManagerName[] = "PulseAudio";
+}
+
 AudioManagerPulse::AudioManagerPulse(
     scoped_refptr<base::SingleThreadTaskRunner> task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> worker_task_runner,
@@ -143,6 +147,10 @@ AudioParameters AudioManagerPulse::GetInputStreamParameters(
                          buffer_size);
 }
 
+const char* AudioManagerPulse::GetName() {
+  return kAudioManagerName;
+}
+
 AudioOutputStream* AudioManagerPulse::MakeLinearOutputStream(
     const AudioParameters& params,
     const LogCallback& log_callback) {