constructor(newReadableStream) {
    super(newReadableStream);

    /**
     * @type {function(!ReadableStreamUnderlyingSource=,
     *     !ReadableStreamStrategy=): !ReadableStream}
     * @override
     */
    this.newReadableStream;
  }
@param {function(!ReadableStreamUnderlyingSource=,
    !ReadableStreamStrategy=): !ReadableStream} newReadableStream