Revert of Enabling audio quality test on mac.

chrome/browser/media/chrome_webrtc_audio_quality_browsertest.cc

Index: chrome/browser/media/chrome_webrtc_audio_quality_browsertest.cc
diff --git a/chrome/browser/media/chrome_webrtc_audio_quality_browsertest.cc b/chrome/browser/media/chrome_webrtc_audio_quality_browsertest.cc
index 20cdf314dad34c6b8a7decd81dc2f6c8121e869b..897649434f40e53178c318f7cef44de0f1c25abc 100644
--- a/chrome/browser/media/chrome_webrtc_audio_quality_browsertest.cc
+++ b/chrome/browser/media/chrome_webrtc_audio_quality_browsertest.cc
@@ -339,10 +339,10 @@
   return true;
 }
 
-#if defined(OS_LINUX) || defined(OS_WIN) || defined(OS_MACOSX)
+#if defined(OS_LINUX) || defined(OS_WIN)
+// Only implemented on Linux and Windows for now.
 #define MAYBE_MANUAL_TestAudioQuality MANUAL_TestAudioQuality
 #else
-// Not implemented on Android, ChromeOS etc.
 #define MAYBE_MANUAL_TestAudioQuality DISABLED_MANUAL_TestAudioQuality
 #endif