Adding cbr support for Opus

webrtc/media/engine/webrtcvoiceengine.cc

Index: webrtc/media/engine/webrtcvoiceengine.cc
diff --git a/webrtc/media/engine/webrtcvoiceengine.cc b/webrtc/media/engine/webrtcvoiceengine.cc
index 4b59a816d8edb5e5baae3f016f3e198094c8a429..d133a39e59e106f7077f4082492a7942f45b1a67 100644
--- a/webrtc/media/engine/webrtcvoiceengine.cc
+++ b/webrtc/media/engine/webrtcvoiceengine.cc
@@ -255,10 +255,12 @@ void GetOpusConfig(const AudioCodec& codec,
                    bool* enable_codec_fec,
                    int* max_playback_rate,
                    bool* enable_codec_dtx,
+                   bool* enable_codec_cbr,
                    int* min_ptime_ms,
                    int* max_ptime_ms) {
   *enable_codec_fec = IsCodecFeatureEnabled(codec, kCodecParamUseInbandFec);
   *enable_codec_dtx = IsCodecFeatureEnabled(codec, kCodecParamUseDtx);
+  *enable_codec_cbr = IsCodecFeatureEnabled(codec, kCodecParamUseCbr);
   *max_playback_rate = GetCodecFeatureInt(codec, kCodecParamMaxPlaybackRate,
                                           kOpusDefaultMaxPlaybackRate);
   *max_ptime_ms =
@@ -1978,6 +1980,7 @@ bool WebRtcVoiceMediaChannel::SetSendCodecs(
                     &send_codec_spec.enable_codec_fec,
                     &send_codec_spec.opus_max_playback_rate,
                     &send_codec_spec.enable_opus_dtx,
+                    &send_codec_spec.enable_opus_cbr,
                     &send_codec_spec.min_ptime_ms,
                     &send_codec_spec.max_ptime_ms);
     }