Fatal error: Uncaught Error: Interface "Drupal\Core\KeyValueStore\KeyValueFactoryInterface" not found in /home/www/drupal8/test/core/lib/Drupal/Core/KeyValueStore/KeyValueFactory.php:10 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/lib/Drupal/Core/KeyValueStore/KeyValueFactory.php on line 10