toJson method Null safety

Implementation

Map<String, dynamic> toJson() {
  final Map<String, dynamic> data = new Map<String, dynamic>();
  data['videoBitrate'] = this.videoBitrate;
  data['videoResolution'] = this.videoResolution;
  data['videoFps'] = this.videoFps;
  data['videoResolutionMode'] = this.videoResolutionMode;
  data['minVideoBitrate'] = this.minVideoBitrate;
  data['enableAdjustRes'] = this.enableAdjustRes;
  return data;
}