Future cancel([Object reason])

Source

Future cancel([Object reason]) {
  if (reason != null) {
    return wrap_jso(_blink.BlinkReadableStreamReader.instance.cancel_Callback_1_(unwrap_jso(this), reason));
  }
  return wrap_jso(_blink.BlinkReadableStreamReader.instance.cancel_Callback_0_(unwrap_jso(this)));
}