diff --git a/core/includes/entity.inc b/core/includes/entity.inc
index eef980e..e12d5df 100644
--- a/core/includes/entity.inc
+++ b/core/includes/entity.inc
@@ -761,7 +761,7 @@ function entity_get_render_display(EntityInterface $entity, $view_mode) {
       $view_mode => 'entity.display.' . $entity->entityType() . '.' . $entity->bundle() . '.' . $view_mode,
     );
     $entity_displays = \Drupal::service('config.storage')->readMultiple($ids);
-    if ($display = $entity_form_displays[$ids[$view_mode]] && $display['status']) {
+    if (isset($entity_displays[$ids[$view_mode]]) && $entity_displays[$ids[$view_mode]]['status']) {
       $render_view_mode = $view_mode;
     }
   }
@@ -861,7 +861,7 @@ function entity_get_render_form_display(EntityInterface $entity, $form_mode) {
       $form_mode => 'entity.form_display.' . $entity->entityType() . '.' . $entity->bundle() . '.' . $form_mode,
     );
     $entity_form_displays = \Drupal::service('config.storage')->readMultiple($ids);
-    if ($form_display = $entity_form_displays[$ids[$form_mode]] && $form_display['status']) {
+    if (isset($entity_form_displays[$ids[$form_mode]]) && $entity_form_displays[$ids[$form_mode]]['status']) {
       $render_form_mode = $form_mode;
     }
   }
diff --git a/core/modules/system/lib/Drupal/system/Tests/Entity/FieldSqlStorageTest.php b/core/modules/system/lib/Drupal/system/Tests/Entity/FieldSqlStorageTest.php
index 34818e0..5efa6b8 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Entity/FieldSqlStorageTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Entity/FieldSqlStorageTest.php
@@ -26,7 +26,7 @@ class FieldSqlStorageTest extends EntityUnitTestBase {
    *
    * @var array
    */
-  public static $modules = array('system', 'field', 'field_test', 'text', 'number', 'entity_test');
+  public static $modules = array('field', 'field_test', 'text', 'number', 'entity_test');
 
   /**
    * The name of the created field.
@@ -67,7 +67,6 @@ public static function getInfo() {
   function setUp() {
     parent::setUp();
     $this->installSchema('entity_test', array('entity_test_rev', 'entity_test_rev_revision'));
-    $this->installSchema('system', array('variable'));
     $entity_type = 'entity_test_rev';
 
     $this->field_name = strtolower($this->randomName());