Ignore -Wdeprecated-declarations in audio_output_mac.cc.

media/audio/mac/audio_output_mac.cc

Index: media/audio/mac/audio_output_mac.cc
diff --git a/media/audio/mac/audio_output_mac.cc b/media/audio/mac/audio_output_mac.cc
index 143d1084cce377bb3f837f4d77f178972b670e1d..b0784ebe6a776042051fec1bedd95e22b7aec7d2 100644
--- a/media/audio/mac/audio_output_mac.cc
+++ b/media/audio/mac/audio_output_mac.cc
@@ -118,6 +118,8 @@ bool PCMQueueOutAudioOutputStream::Open() {
   // TODO(annacc): AudioDeviceGetPropertyInfo() is deprecated, but its
   // replacement, AudioObjectGetPropertyDataSize(), doesn't work yet with
   // kAudioDevicePropertyPreferredChannelLayout.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
   err = AudioDeviceGetPropertyInfo(device_id, 0, false,
                                    kAudioDevicePropertyPreferredChannelLayout,
                                    &core_layout_size, NULL);
@@ -141,6 +143,7 @@ bool PCMQueueOutAudioOutputStream::Open() {
     HandleError(err);
     return false;
   }
+#pragma clang diagnostic pop
 
   num_core_channels_ =
       static_cast<int>(core_channel_layout->mNumberChannelDescriptions);