diff --git a/core/modules/serialization/src/Tests/NormalizerTestBase.php b/core/modules/serialization/src/Tests/NormalizerTestBase.php
index c38c554..c7fa29a 100644
--- a/core/modules/serialization/src/Tests/NormalizerTestBase.php
+++ b/core/modules/serialization/src/Tests/NormalizerTestBase.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\serialization\Tests;
 
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 abstract class NormalizerTestBase extends KernelTestBase {
 
@@ -29,14 +29,18 @@ protected function setUp() {
     \Drupal::moduleHandler()->invoke('rest', 'install');
 
     // Auto-create a field for testing.
-    entity_create('field_storage_config', array(
+    \Drupal::entityManager()
+        ->getStorage('field_storage_config')
+        ->create(array(
       'entity_type' => 'entity_test_mulrev',
       'field_name' => 'field_test_text',
       'type' => 'text',
       'cardinality' => 1,
       'translatable' => FALSE,
     ))->save();
-    entity_create('field_config', array(
+    \Drupal::entityManager()
+        ->getStorage('field_config')
+        ->create(array(
       'entity_type' => 'entity_test_mulrev',
       'field_name' => 'field_test_text',
       'bundle' => 'entity_test_mulrev',