start method
Implementation
Future<void> start() async {
rtcPeerConnection =
await createPeerConnection(configuration, loopbackConstraints);
rtcPeerConnection?.addStream(localStream!);
rtcPeerConnection?.onAddStream = _onAddStream;
rtcPeerConnection?.onRemoveStream = _onRemoveStream;
rtcPeerConnection?.onRenegotiationNeeded = _onRenegotiationNeeded;
rtcPeerConnection?.onIceCandidate = _onIceCandidate;
await renderer!.initialize();
this.emit('connected');
}