RouterTestBundle.php

<?php

/**
 * @file
 * Definition of \Drupal\router_test\RouterTestBundle.
 */
namespace Drupal\router_test;

use Symfony\Component\DependencyInjection\ContainerBuilder;
use Symfony\Component\HttpKernel\Bundle\Bundle;

/**
 * Registers a dynamic route provider.
 */
class RouterTestBundle extends Bundle {

  /**
   * Overrides Symfony\Component\HttpKernel\Bundle\Bundle::build().
   */
  public function build(ContainerBuilder $container) {
    $container
      ->register('router_test.subscriber', 'Drupal\\router_test\\RouteTestSubscriber')
      ->addTag('event_subscriber');
  }

}