diff -u b/core/modules/system/lib/Drupal/system/Tests/Cache/DatabaseBackendUnitTest.php b/core/modules/system/lib/Drupal/system/Tests/Cache/DatabaseBackendUnitTest.php
--- b/core/modules/system/lib/Drupal/system/Tests/Cache/DatabaseBackendUnitTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Cache/DatabaseBackendUnitTest.php
@@ -15,6 +15,13 @@
  */
 class DatabaseBackendUnitTest extends GenericCacheBackendUnitTestBase {
 
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = array('system');
+
   public static function getInfo() {
     return array(
       'name' => 'Database backend',
@@ -37,12 +44,7 @@
    * Installs system schema.
    */
   public function setUpCacheBackend() {
-    // Calling drupal_install_schema() entails a call to module_invoke, for which
-    // we need a ModuleHandler. Register one to the container.
-    // @todo Use DrupalUnitTestBase.
-    $this->container->register('module_handler', 'Drupal\Core\Extension\ModuleHandler');
-
-    drupal_install_schema('system');
+    $this->installSchema('system', array('cache', 'cache_page', 'cache_tags', 'cache_path', 'cache_bootstrap'));
   }
 
   /**
diff -u b/core/modules/system/system.module b/core/modules/system/system.module
--- b/core/modules/system/system.module
+++ b/core/modules/system/system.module
@@ -3532,10 +3532,9 @@
   Drupal::service('flood')->garbageCollection();
 
   module_invoke_all('cache_flush');
-  $bins = Cache::getBins();
-  array_walk($bins, function (CacheBackendInterface $cache_backend) {
+  foreach (Cache::getBins() as $cache_backend) {
     $cache_backend->deleteExpired();
-  });
+  }
 
   // Cleanup the batch table and the queue for failed batches.
   db_delete('batch')
only in patch2:
unchanged:
--- a/core/modules/system/lib/Drupal/system/Tests/Cache/GenericCacheBackendUnitTestBase.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Cache/GenericCacheBackendUnitTestBase.php
@@ -8,7 +8,7 @@
 namespace Drupal\system\Tests\Cache;
 
 use Drupal\Core\Cache\CacheBackendInterface;
-use Drupal\simpletest\UnitTestBase;
+use Drupal\simpletest\DrupalUnitTestBase;
 
 use stdClass;
 
@@ -22,7 +22,7 @@
  * @see DatabaseBackendUnitTestCase
  *   For a full working implementation.
  */
-abstract class GenericCacheBackendUnitTestBase extends UnitTestBase {
+abstract class GenericCacheBackendUnitTestBase extends DrupalUnitTestBase {
 
   /**
    * Array of objects implementing Drupal\Core\Cache\CacheBackendInterface.