diff --git a/core/modules/system/tests/modules/entity_test/src/Entity/EntityTestUpdate.php b/core/modules/system/tests/modules/entity_test/src/Entity/EntityTestUpdate.php
deleted file mode 100644
index 6d72f7a..0000000
--- a/core/modules/system/tests/modules/entity_test/src/Entity/EntityTestUpdate.php
+++ /dev/null
@@ -1,51 +0,0 @@
-<?php
-
-namespace Drupal\entity_test\Entity;
-
-use Drupal\Core\Entity\EntityTypeInterface;
-
-/**
- * Defines the test entity class for testing definition updates.
- *
- * This entity type starts out non-revisionable by lacking a "revision_id" key,
- * but during an update test, can be made revisionable by adding that key.
- *
- * @ContentEntityType(
- *   id = "entity_test_update",
- *   label = @Translation("Test entity update"),
- *   handlers = {
- *     "storage_schema" = "Drupal\entity_test\EntityTestStorageSchema"
- *   },
- *   base_table = "entity_test_update",
- *   revision_table = "entity_test_update_revision",
- *   persistent_cache = FALSE,
- *   entity_keys = {
- *     "id" = "id",
- *     "uuid" = "uuid",
- *     "bundle" = "type",
- *     "label" = "name",
- *     "langcode" = "langcode",
- *   }
- * )
- */
-class EntityTestUpdate extends EntityTestRev {
-
-  /**
-   * {@inheritdoc}
-   */
-  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
-    $fields = parent::baseFieldDefinitions($entity_type);
-    $fields += \Drupal::state()->get('entity_test_update.additional_base_field_definitions', []);
-    return $fields;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public static function bundleFieldDefinitions(EntityTypeInterface $entity_type, $bundle, array $base_field_definitions) {
-    $fields = parent::bundleFieldDefinitions($entity_type, $bundle, $base_field_definitions);
-    $fields += \Drupal::state()->get('entity_test_update.additional_bundle_field_definitions.' . $bundle, []);
-    return $fields;
-  }
-
-}
diff --git a/core/modules/system/tests/modules/entity_test_update/src/Entity/EntityTestUpdate.php b/core/modules/system/tests/modules/entity_test_update/src/Entity/EntityTestUpdate.php
index 0de2460..e2bec61 100644
--- a/core/modules/system/tests/modules/entity_test_update/src/Entity/EntityTestUpdate.php
+++ b/core/modules/system/tests/modules/entity_test_update/src/Entity/EntityTestUpdate.php
@@ -57,12 +57,14 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
       ->setLabel(new TranslatableMarkup('ID'))
       ->setDescription(new TranslatableMarkup('The ID of the test entity.'))
       ->setReadOnly(TRUE)
+      ->setStorageRequired(TRUE)
       ->setSetting('unsigned', TRUE);
 
     $fields[$entity_type->getKey('uuid')] = BaseFieldDefinition::create('uuid')
       ->setLabel(new TranslatableMarkup('UUID'))
       ->setDescription(new TranslatableMarkup('The UUID of the test entity.'))
-      ->setReadOnly(TRUE);
+      ->setReadOnly(TRUE)
+      ->setStorageRequired(TRUE);
 
     $fields[$entity_type->getKey('bundle')] = BaseFieldDefinition::create('string')
       ->setLabel(new TranslatableMarkup('Type'))
@@ -77,7 +79,8 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
     }
 
     $fields[$entity_type->getKey('langcode')] = BaseFieldDefinition::create('language')
-      ->setLabel(new TranslatableMarkup('Language'));
+      ->setLabel(new TranslatableMarkup('Language'))
+      ->setStorageRequired(TRUE);
     if ($entity_type->isRevisionable()) {
       $fields[$entity_type->getKey('langcode')]->setRevisionable(TRUE);
     }