Method createError

third_party/subscriptions-project/config.js:565–572

* Creates an error. * @param {...*} var_args * @return {!Error}

(var_args)

   * @return {!Error}
   */
  createError(var_args) {
    const error = createErrorVargs.apply(
      null,
      Array.prototype.slice.call(arguments)
    );
    this.prepareError_(error);
    return error;
  }

  /**
   * Creates an error object with its expected property set to true. Used for