Fatal error: Uncaught Error: Class "Drupal\Core\Field\Plugin\Field\FieldType\LanguageItem" not found in /home/www/drupal8/test/core/modules/language/src/DefaultLanguageItem.php:20 Stack trace: #0 {main} thrown in /home/www/drupal8/test/core/modules/language/src/DefaultLanguageItem.php on line 20