constructor() {
    /**
     * A map of extra runtime module dependencies.
     * @type {!AbstractModuleLoader.ExtraEdgesMap|undefined}
     */
    this.extraEdges;

    /**
     * Whether to bypass cache while loading the module.
     * @const {boolean|undefined}
     */
    this.forceReload;

    /**
     * The callback if module loading is an error.
     * @const {(function(?number): void)|undefined}
     */
    this.onError;

    /**
     * The callback if module loading is a success.
     * @const {(function(): void)|undefined}
     */
    this.onSuccess;

    /**
     * The callback if module loading times out.
     * @const {(function(): void)|undefined}
     */
    this.onTimeout;
  }
Optional parameters for the loadModules method.
@record