connect method
      
void
connect()
      
     
    
    
Implementation
void connect() {
  logger.debug('connect()');
  if (isConnected()) {
    logger.debug('Transport is already connected');
    return;
  } else if (isConnecting()) {
    logger.debug('Transport is connecting');
    return;
  }
  _close_requested = false;
  status = C.STATUS_CONNECTING;
  onconnecting(socket, _recover_attempts);
  if (!_close_requested) {
    // Bind socket event callbacks.
    socket!.onconnect = _onConnect;
    socket!.ondisconnect = _onDisconnect;
    socket!.ondata = _onData;
    socket!.connect();
  }
  return;
}