code: func NewXHRSession(opts *DialOptions) (*XHRSession, error) {
  	cfg := config.New()
  	cfg.XHR = opts.client()
  
  	return DialXHR(opts.BaseURL, cfg)
  }
docs: // NewXHRSession returns a new XHRSession, a SockJS client which supports xhr-polling:
  //
  //   http://sockjs.github.io/sockjs-protocol/sockjs-protocol-0.3.3.html#section-74
  //
  // Deprecated: Use DialXHR instead.