Function shutdown

lib/internal/webstreams/readablestream.js:1537–1549

(rejected, error)

  }

  function shutdown(rejected, error) {
    if (shuttingDown) return;
    shuttingDown = true;
    if (dest[kState].state === 'writable' &&
        !writableStreamCloseQueuedOrInFlight(dest)) {
      PromisePrototypeThen(
        waitForCurrentWrite(),
        () => finalize(rejected, error),
        (error) => finalize(true, error));
      return;
    }
    finalize(rejected, error);
  }

  function abortAlgorithm() {
    let error;