code: function WritableStreamDefaultControllerAbort(controller, reason) {
    controller._queue = [];
  
    const sinkAbortPromise = PromiseInvokeOrFallbackOrNoop(controller._underlyingSink, 'abort', [reason],
                                                           'close', [controller]);
    return sinkAbortPromise.then(() => undefined);
  }
docs: Abstract operations implementing interface required by the WritableStream.