Fatal error: Uncaught Error: Interface "Drupal\Core\Entity\EntityFormBuilderInterface" not found in /home/www/drupal8/test/core/lib/Drupal/Core/Entity/EntityFormBuilder.php:11 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/lib/Drupal/Core/Entity/EntityFormBuilder.php on line 11