Fatal error: Uncaught Error: Interface "Symfony\Component\Translation\TranslatorInterface" not found in /home/www/drupal8/test/core/lib/Drupal/Core/Validation/TranslatorInterface.php:17 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/lib/Drupal/Core/Validation/TranslatorInterface.php on line 17