Fatal error: Uncaught Error: Class "Drupal\Core\Routing\RouteSubscriberBase" not found in /home/www/drupal8/test/core/modules/content_translation/src/Routing/ContentTranslationRouteSubscriber.php:15 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/modules/content_translation/src/Routing/ContentTranslationRouteSubscriber.php on line 15