Move functionality out from AudioFrame and into AudioFrameOperations.

webrtc/voice_engine/voe_external_media_impl.cc

Index: webrtc/voice_engine/voe_external_media_impl.cc
diff --git a/webrtc/voice_engine/voe_external_media_impl.cc b/webrtc/voice_engine/voe_external_media_impl.cc
index 6f02495e5c578453388779d2e0ef2c696faa3505..85305c82243242e35bf35b42ae988b7a4e8d9dbc 100644
--- a/webrtc/voice_engine/voe_external_media_impl.cc
+++ b/webrtc/voice_engine/voe_external_media_impl.cc
@@ -10,6 +10,7 @@
 
 #include "webrtc/voice_engine/voe_external_media_impl.h"
 
+#include "webrtc/audio/utility/audio_frame_operations.h"
 #include "webrtc/system_wrappers/include/trace.h"
 #include "webrtc/voice_engine/channel.h"
 #include "webrtc/voice_engine/include/voe_errors.h"
@@ -149,7 +150,7 @@ int VoEExternalMediaImpl::GetAudioFrame(int channel, int desired_sample_rate_hz,
       desired_sample_rate_hz == 0 ? -1 : desired_sample_rate_hz;
   auto ret = channelPtr->GetAudioFrameWithMuted(channel, frame);
   if (ret == MixerParticipant::AudioFrameInfo::kMuted) {
-    frame->Mute();
+    AudioFrameOperations::Mute(frame);
   }
   return ret == MixerParticipant::AudioFrameInfo::kError ? -1 : 0;
 }