edlp_d8/core/lib/Drupal/Core/Installer/InstallerRouteBuilder.php

<?php

namespace Drupal\Core\Installer;

use Drupal\Core\Routing\RouteBuilder;

/**
 * Manages the router in the installer.
 */
class InstallerRouteBuilder extends RouteBuilder {

  /**
   * {@inheritdoc}
   *
   * Overridden to return no routes.
   *
   * @todo Convert installer steps into routes; add an installer.routing.yml.
   */
  protected function getRouteDefinitions() {
    return [];
  }

}