diff --git a/core/core.services.yml b/core/core.services.yml
index 1449b3b..d716015 100644
--- a/core/core.services.yml
+++ b/core/core.services.yml
@@ -7,8 +7,6 @@ services:
   cache.backend.database:
     class: Drupal\Core\Cache\DatabaseBackendFactory
     arguments: ['@database']
-  cache.backend.memory:
-    class: Drupal\Core\Cache\MemoryBackendFactory
   cache.bootstrap:
     class: Drupal\Core\Cache\CacheBackendInterface
     tags:
diff --git a/core/lib/Drupal/Core/DependencyInjection/UpdateServiceProvider.php b/core/lib/Drupal/Core/DependencyInjection/UpdateServiceProvider.php
index ee637ea..293474c 100644
--- a/core/lib/Drupal/Core/DependencyInjection/UpdateServiceProvider.php
+++ b/core/lib/Drupal/Core/DependencyInjection/UpdateServiceProvider.php
@@ -36,7 +36,7 @@ public function register(ContainerBuilder $container) {
     $container->register('module_handler', 'Drupal\Core\Extension\UpdateModuleHandler')
       ->addArgument('%container.modules%');
     $container
-      ->register("cache_factory", 'Drupal\Core\Cache\MemoryBackendFactory');
+      ->register('cache_factory', 'Drupal\Core\Cache\MemoryBackendFactory');
     $container
       ->register('router.builder', 'Drupal\Core\Routing\RouteBuilderStatic');
 
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php
index 879ca80..88090d4 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/DrupalUnitTestBase.php
@@ -147,7 +147,7 @@ public function containerBuild(ContainerBuilder $container) {
     $this->container = $container;
 
     $container->register('lock', 'Drupal\Core\Lock\NullLockBackend');
-    $this->settingsSet('cache', array('default' => 'cache.backend.memory'));
+    $container->register('cache_factory', 'Drupal\Core\Cache\MemoryBackendFactory');
 
     $container
       ->register('config.storage', 'Drupal\Core\Config\FileStorage')
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
index 265012e..a9eed2a 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
@@ -752,6 +752,7 @@ protected function setUp() {
     // search path to the child site's search paths.
     // @see drupal_system_listing()
     $conf['simpletest_parent_profile'] = $this->originalProfile;
+    $conf['container_service_providers']['WebTestServiceProvider'] = 'Drupal\simpletest\WebTestServiceProvider';
 
     // Define information about the user 1 account.
     $this->root_user = new UserSession(array(
@@ -778,6 +779,7 @@ protected function setUp() {
         NestedArray::setValue($GLOBALS['conf'], array_merge(array($config_base), explode('.', $name)), $value);
       }
     }
+
     $this->settingsSet('file_public_path', $this->public_files_directory);
     // Execute the non-interactive installer.
     require_once DRUPAL_ROOT . '/core/includes/install.core.inc';
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/WebTestServiceProvider.php b/core/modules/simpletest/lib/Drupal/simpletest/WebTestServiceProvider.php
new file mode 100644
index 0000000..d00625c
--- /dev/null
+++ b/core/modules/simpletest/lib/Drupal/simpletest/WebTestServiceProvider.php
@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\simpletest\WebTestServiceProvider.
+ */
+
+namespace Drupal\simpletest;
+
+use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\Core\DependencyInjection\ServiceProviderInterface;
+
+/**
+ * Service provider for web tests.
+ */
+class WebTestServiceProvider implements ServiceProviderInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  function register(ContainerBuilder $container) {
+    // Add the memory backend cache factory.
+    $container->register('cache.backend.memory', 'Drupal\Core\Cache\MemoryBackendFactory');
+  }
+
+}