Abstract operations implementing interface required by the WritableStream.
function WritableStreamDefaultControllerAbort(controller, reason) {
  controller._queue = [];

  const sinkAbortPromise = PromiseInvokeOrFallbackOrNoop(controller._underlyingSink, 'abort', [reason],
                                                         'close', [controller]);
  return sinkAbortPromise.then(() => undefined);
}