diff --git a/core/modules/system/tests/modules/entity_test/entity_test.module b/core/modules/system/tests/modules/entity_test/entity_test.module
index 7e14f56f73..a2f4e9f577 100644
--- a/core/modules/system/tests/modules/entity_test/entity_test.module
+++ b/core/modules/system/tests/modules/entity_test/entity_test.module
@@ -19,7 +19,7 @@
 use Drupal\Core\Session\AccountInterface;
 use Drupal\Core\Entity\Entity\EntityFormDisplay;
 use Drupal\Core\Url;
-use Drupal\entity_test\Entity\EntityTestKeys;
+use Drupal\entity_test\Entity\EntityTest;
 
 /**
  * Filter that limits test entity list to revisable ones.
@@ -103,8 +103,8 @@ function entity_test_entity_type_alter(array &$entity_types) {
     unset($entity_types['entity_test_new']);
   }
 
-  $entity_test_keys_definition = $entity_types['entity_test_keys'];
-  $entity_test_keys_definition->set('entity_keys', $state->get('entity_test_keys.entity_keys', EntityTestKeys::defaultEntityKeys()));
+  $entity_test_definition = $entity_types['entity_test'];
+  $entity_test_definition->set('entity_keys', $state->get('entity_test.entity_keys', EntityTest::defaultEntityKeys()));
 }
 
 /**
diff --git a/core/modules/system/tests/modules/entity_test/src/Entity/EntityTest.php b/core/modules/system/tests/modules/entity_test/src/Entity/EntityTest.php
index 9f8c5b0521..77b295f6ae 100644
--- a/core/modules/system/tests/modules/entity_test/src/Entity/EntityTest.php
+++ b/core/modules/system/tests/modules/entity_test/src/Entity/EntityTest.php
@@ -33,13 +33,7 @@
  *   admin_permission = "administer entity_test content",
  *   persistent_cache = FALSE,
  *   list_cache_contexts = { "entity_test_view_grants" },
- *   entity_keys = {
- *     "id" = "id",
- *     "uuid" = "uuid",
- *     "bundle" = "type",
- *     "label" = "name",
- *     "langcode" = "langcode",
- *   },
+ *   entity_keys = {},
  *   links = {
  *     "canonical" = "/entity_test/{entity_test}",
  *     "add-form" = "/entity_test/add",
@@ -109,7 +103,7 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
         ],
       ]);
 
-    return $fields;
+    return $fields + \Drupal::state()->get($entity_type->id() . '.additional_base_field_definitions', []);;
   }
 
   /**
@@ -164,4 +158,31 @@ public function getName() {
     return $this->get('name')->value;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getEntityKey($key) {
+    return parent::getEntityKey($key);
+  }
+
+  /**
+   * Default entity keys used for a working entity type.
+   *
+   * @return array
+   *   An array of entity keys.
+   *
+   * @see entity_test_entity_type_alter
+   */
+  public static function defaultEntityKeys() {
+    return [
+      'id' => 'id',
+      'uuid' => 'uuid',
+      'bundle' => 'type',
+      'label' => 'name',
+      'langcode' => 'langcode',
+      'default_langcode' => 'default_langcode',
+      'revision_translation_affected' => 'revision_translation_affected',
+    ];
+  }
+
 }
diff --git a/core/modules/system/tests/modules/entity_test/src/Entity/EntityTestKeys.php b/core/modules/system/tests/modules/entity_test/src/Entity/EntityTestKeys.php
deleted file mode 100644
index 290bd896b0..0000000000
--- a/core/modules/system/tests/modules/entity_test/src/Entity/EntityTestKeys.php
+++ /dev/null
@@ -1,76 +0,0 @@
-<?php
-
-namespace Drupal\entity_test\Entity;
-
-use Drupal\Core\Entity\EntityTypeInterface;
-
-/**
- * Defines a test entity class with test-configurable keys and fields.
- *
- * @ContentEntityType(
- *   id = "entity_test_keys",
- *   label = @Translation("Test entity - entity keys"),
- *   handlers = {
- *     "view_builder" = "Drupal\entity_test\EntityTestViewBuilder",
- *     "access" = "Drupal\entity_test\EntityTestAccessControlHandler",
- *     "form" = {
- *       "default" = "Drupal\entity_test\EntityTestForm",
- *       "delete" = "Drupal\entity_test\EntityTestDeleteForm"
- *     },
- *     "translation" = "Drupal\content_translation\ContentTranslationHandler",
- *     "views_data" = "Drupal\views\EntityViewsData",
- *     "route_provider" = {
- *       "html" = "Drupal\Core\Entity\Routing\DefaultHtmlRouteProvider",
- *     },
- *   },
- *   base_table = "entity_test_keys",
- *   data_table = "entity_test_keys_property_data",
- *   admin_permission = "administer entity_test content",
- *   translatable = TRUE,
- *   entity_keys = {},
- *   links = {
- *     "add-page" = "/entity_test_keys/add",
- *     "add-form" = "/entity_test_keys/add/{type}",
- *     "canonical" = "/entity_test_keys/{entity_test_keys}",
- *     "edit-form" = "/entity_test_keys/{entity_test_keys}/edit",
- *     "delete-form" = "/entity_test_keys/{entity_test_keys}/delete",
- *   }
- * )
- */
-class EntityTestKeys extends EntityTest {
-
-  /**
-   * {@inheritdoc}
-   */
-  public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
-    return parent::baseFieldDefinitions($entity_type) + \Drupal::state()->get($entity_type->id() . '.additional_base_field_definitions', []);
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  public function getEntityKey($key) {
-    return parent::getEntityKey($key);
-  }
-
-  /**
-   * Default entity keys used for a working entity type.
-   *
-   * @return array
-   *   An array of entity keys.
-   *
-   * @see entity_test_entity_type_alter
-   */
-  public static function defaultEntityKeys() {
-    return [
-      'id' => 'id',
-      'uuid' => 'uuid',
-      'revision' => 'revision_id',
-      'label' => 'name',
-      'langcode' => 'langcode',
-      'default_langcode' => 'default_langcode',
-      'revision_translation_affected' => 'revision_translation_affected',
-    ];
-  }
-
-}
diff --git a/core/tests/Drupal/KernelTests/Core/Entity/EntityKeysTest.php b/core/tests/Drupal/KernelTests/Core/Entity/EntityKeysTest.php
index 03dc8b5c31..f799da7c35 100644
--- a/core/tests/Drupal/KernelTests/Core/Entity/EntityKeysTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Entity/EntityKeysTest.php
@@ -3,7 +3,7 @@
 namespace Drupal\KernelTests\Core\Entity;
 
 use Drupal\Core\Field\BaseFieldDefinition;
-use Drupal\entity_test\Entity\EntityTestKeys;
+use Drupal\entity_test\Entity\EntityTest;
 
 /**
  * Test the behavior of entity keys.
@@ -18,7 +18,7 @@ class EntityKeysTest extends EntityKernelTestBase {
    * @dataProvider multipleKeysCacheTestCases
    */
   public function testMultipleKeysCache($translatable) {
-    $this->state->set('entity_test_keys.additional_base_field_definitions', [
+    $this->state->set('entity_test.additional_base_field_definitions', [
       'test_field' => BaseFieldDefinition::create('string')->setTranslatable($translatable),
     ]);
     $this->setupTestEntityKeys([
@@ -26,9 +26,9 @@ public function testMultipleKeysCache($translatable) {
       'key_2' => 'test_field',
     ]);
     drupal_flush_all_caches();
-    $this->installEntitySchema('entity_test_keys');
+    $this->installEntitySchema('entity_test');
 
-    $entity = EntityTestKeys::create([]);
+    $entity = EntityTest::create([]);
 
     $entity->set('test_field', 'foo');
     $this->assertEquals('foo', $entity->getEntityKey('key_1'));
@@ -60,7 +60,7 @@ public function multipleKeysCacheTestCases() {
    *   Keys to set.
    */
   protected function setupTestEntityKeys($keys) {
-    $this->state->set('entity_test_keys.entity_keys', EntityTestKeys::defaultEntityKeys() + $keys);
+    $this->state->set('entity_test.entity_keys', EntityTest::defaultEntityKeys() + $keys);
   }
 
 }