Fatal error: Uncaught Error: Interface "Drupal\Core\Validation\TranslatorInterface" not found in /home/www/drupal8/test/core/lib/Drupal/Core/Validation/DrupalTranslator.php:13 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/lib/Drupal/Core/Validation/DrupalTranslator.php on line 13