Log audio system used to WebRTC log.

media/audio/mac/audio_manager_mac.cc

Index: media/audio/mac/audio_manager_mac.cc
diff --git a/media/audio/mac/audio_manager_mac.cc b/media/audio/mac/audio_manager_mac.cc
index 14877a95f92eb8321907344a80187c9c9ae63a5f..006d80b48d41562c73a815d99b217fb3dba83ac9 100644
--- a/media/audio/mac/audio_manager_mac.cc
+++ b/media/audio/mac/audio_manager_mac.cc
@@ -40,6 +40,8 @@ static const int kMaximumInputOutputBufferSize = 4096;
 // Default sample-rate on most Apple hardware.
 static const int kFallbackSampleRate = 44100;
 
+const char kAudioManagerName[] = "Mac";
+
 // Helper method to construct AudioObjectPropertyAddress structure given
 // property selector and scope. The property element is always set to
 // kAudioObjectPropertyElementMaster.
@@ -603,6 +605,10 @@ std::string AudioManagerMac::GetAssociatedOutputDeviceID(
   return std::string();
 }
 
+const char* AudioManagerMac::GetName() {
+  return kAudioManagerName;
+}
+
 AudioOutputStream* AudioManagerMac::MakeLinearOutputStream(
     const AudioParameters& params,
     const LogCallback& log_callback) {