Adding OnReceivedOverhead to AudioEncoder.

webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.cc

Index: webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.cc
diff --git a/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.cc b/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.cc
index 0f0958c2dca68f922ee903f2132fa0ea5d0a671e..4f72f6b93e1cb3ae21cfc7933b62b5f827e078c4 100644
--- a/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.cc
+++ b/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus.cc
@@ -326,6 +326,13 @@ void AudioEncoderOpus::OnReceivedRtt(int rtt_ms) {
   ApplyAudioNetworkAdaptor();
 }
 
+void AudioEncoderOpus::OnReceivedOverhead(size_t overhead_bytes_per_packet) {
+  if (!audio_network_adaptor_)
+    return;
+  audio_network_adaptor_->SetOverhead(overhead_bytes_per_packet);
+  ApplyAudioNetworkAdaptor();
+}
+
 void AudioEncoderOpus::SetReceiverFrameLengthRange(int min_frame_length_ms,
                                                    int max_frame_length_ms) {
   // Ensure that |SetReceiverFrameLengthRange| is called before