addSimulcastTrack method
- String codec,
- List<RTCRtpEncoding> encodings
Implementation
SimulcastTrackInfo addSimulcastTrack(
    String codec, List<rtc.RTCRtpEncoding> encodings) {
  if (simulcastCodecs[codec] != null) {
    throw Exception('$codec already added');
  }
  SimulcastTrackInfo simulcastCodecInfo = SimulcastTrackInfo(
    codec: codec,
    encodings: encodings,
    mediaStreamTrack: mediaStreamTrack,
  );
  simulcastCodecs[codec] = simulcastCodecInfo;
  return simulcastCodecInfo;
}