StreamManager constructor Null safety

Implementation

StreamManager() {
  _totalUnreadCountController = StreamController<int>.broadcast();
  _messageUpdateStreamController =
      StreamController<ChannelMessageResponse>.broadcast();
  _messageReceiveStreamController =
      StreamController<ChannelMessageResponse>.broadcast();
  _messageDeleteStreamController =
      StreamController<ChannelMessageResponse>.broadcast();
  _channelChangedStreamController = StreamController<BaseChannel>.broadcast();
  _readStreamController = StreamController<GroupChannel>.broadcast();
  _deliveryStreamController = StreamController<GroupChannel>.broadcast();
  _usersTypingStreamController = StreamController<GroupChannel>.broadcast();
  _connectionStreamController =
      StreamController<ConnectionEventType>.broadcast();
}