only in patch2:
unchanged:
--- a/core/modules/hal/tests/src/Kernel/FileNormalizeTest.php
+++ b/core/modules/hal/tests/src/Kernel/FileNormalizeTest.php
@@ -2,6 +2,7 @@
 
 namespace Drupal\Tests\hal\Kernel;
 
+use Drupal\Component\Serialization\PhpSerialize;
 use Drupal\Core\Cache\MemoryBackend;
 use Drupal\file\Entity\File;
 use Drupal\hal\Encoder\JsonEncoder;
@@ -35,7 +36,7 @@ protected function setUp() {
     $this->installEntitySchema('file');
 
     $entity_manager = \Drupal::entityManager();
-    $link_manager = new LinkManager(new TypeLinkManager(new MemoryBackend(), \Drupal::moduleHandler(), \Drupal::service('config.factory'), \Drupal::service('request_stack'), \Drupal::service('entity_type.bundle.info')), new RelationLinkManager(new MemoryBackend(), $entity_manager, \Drupal::moduleHandler(), \Drupal::service('config.factory'), \Drupal::service('request_stack')));
+    $link_manager = new LinkManager(new TypeLinkManager(new MemoryBackend(new PhpSerialize()), \Drupal::moduleHandler(), \Drupal::service('config.factory'), \Drupal::service('request_stack'), \Drupal::service('entity_type.bundle.info')), new RelationLinkManager(new MemoryBackend(), $entity_manager, \Drupal::moduleHandler(), \Drupal::service('config.factory'), \Drupal::service('request_stack')));
 
     // Set up the mock serializer.
     $normalizers = array(
only in patch2:
unchanged:
--- a/core/modules/hal/tests/src/Kernel/NormalizerTestBase.php
+++ b/core/modules/hal/tests/src/Kernel/NormalizerTestBase.php
@@ -2,6 +2,7 @@
 
 namespace Drupal\Tests\hal\Kernel;
 
+use Drupal\Component\Serialization\PhpSerialize;
 use Drupal\Core\Cache\MemoryBackend;
 use Drupal\field\Entity\FieldConfig;
 use Drupal\hal\Encoder\JsonEncoder;
@@ -131,7 +132,8 @@ protected function setUp() {
     ])->save();
 
     $entity_manager = \Drupal::entityManager();
-    $link_manager = new LinkManager(new TypeLinkManager(new MemoryBackend(), \Drupal::moduleHandler(), \Drupal::service('config.factory'), \Drupal::service('request_stack'), \Drupal::service('entity_type.bundle.info')), new RelationLinkManager(new MemoryBackend(), $entity_manager, \Drupal::moduleHandler(), \Drupal::service('config.factory'), \Drupal::service('request_stack')));
+    $php_serialize = new PhpSerialize();
+    $link_manager = new LinkManager(new TypeLinkManager(new MemoryBackend($php_serialize), \Drupal::moduleHandler(), \Drupal::service('config.factory'), \Drupal::service('request_stack'), \Drupal::service('entity_type.bundle.info')), new RelationLinkManager(new MemoryBackend($php_serialize), $entity_manager, \Drupal::moduleHandler(), \Drupal::service('config.factory'), \Drupal::service('request_stack')));
 
     $chain_resolver = new ChainEntityResolver(array(new UuidResolver($entity_manager), new TargetIdResolver()));
 
only in patch2:
unchanged:
--- a/core/tests/Drupal/KernelTests/Core/Plugin/PluginTestBase.php
+++ b/core/tests/Drupal/KernelTests/Core/Plugin/PluginTestBase.php
@@ -2,6 +2,7 @@
 
 namespace Drupal\KernelTests\Core\Plugin;
 
+use Drupal\Component\Serialization\PhpSerialize;
 use Drupal\Core\Plugin\Context\ContextDefinition;
 use Drupal\KernelTests\KernelTestBase;
 use Drupal\plugin_test\Plugin\TestPluginManager;
@@ -42,7 +43,7 @@ protected function setUp() {
     //   as derivatives and ReflectionFactory.
     $this->testPluginManager = new TestPluginManager();
     $this->mockBlockManager = new MockBlockManager();
-    $module_handler = new ModuleHandler(\Drupal::root(), array(), new MemoryBackend(), $this->container->get('event_dispatcher'));
+    $module_handler = new ModuleHandler(\Drupal::root(), array(), new MemoryBackend(new PhpSerialize()), $this->container->get('event_dispatcher'));
     $this->defaultsTestPluginManager = new DefaultsTestPluginManager($module_handler);
 
     // The expected plugin definitions within each manager. Several tests assert
only in patch2:
unchanged:
--- a/core/tests/Drupal/KernelTests/Core/Routing/RouteProviderTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Routing/RouteProviderTest.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\KernelTests\Core\Routing;
 
+use Drupal\Component\Serialization\PhpSerialize;
 use Drupal\Core\Cache\MemoryBackend;
 use Drupal\Core\Database\Database;
 use Drupal\Core\DependencyInjection\ContainerBuilder;
@@ -83,7 +84,7 @@ protected function setUp() {
     $this->fixtures = new RoutingFixtures();
     $this->state = new State(new KeyValueMemoryFactory());
     $this->currentPath = new CurrentPathStack(new RequestStack());
-    $this->cache = new MemoryBackend();
+    $this->cache = new MemoryBackend(new PhpSerialize());
     $this->pathProcessor = \Drupal::service('path_processor_manager');
     $this->cacheTagsInvalidator = \Drupal::service('cache_tags.invalidator');
   }
only in patch2:
unchanged:
--- a/core/tests/Drupal/Tests/Core/Render/RendererBubblingTest.php
+++ b/core/tests/Drupal/Tests/Core/Render/RendererBubblingTest.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\Tests\Core\Render;
 
+use Drupal\Component\Serialization\PhpSerialize;
 use Drupal\Core\Cache\MemoryBackend;
 use Drupal\Core\KeyValueStore\KeyValueMemoryFactory;
 use Drupal\Core\State\State;
@@ -79,8 +80,9 @@ public function testContextBubblingCustomCacheBin() {
     $bin = $this->randomMachineName();
 
     $this->setUpRequest();
-    $this->memoryCache = new MemoryBackend();
-    $custom_cache = new MemoryBackend();
+    $php_serialize = new PhpSerialize();
+    $this->memoryCache = new MemoryBackend($php_serialize);
+    $custom_cache = new MemoryBackend($php_serialize);
 
     $this->cacheFactory->expects($this->atLeastOnce())
       ->method('get')
only in patch2:
unchanged:
--- a/core/tests/Drupal/Tests/Core/Render/RendererTestBase.php
+++ b/core/tests/Drupal/Tests/Core/Render/RendererTestBase.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\Tests\Core\Render;
 
+use Drupal\Component\Serialization\PhpSerialize;
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Cache\Context\ContextCacheKeys;
@@ -208,7 +209,7 @@ protected function setUpUnusedCache() {
    * Sets up a memory-based render cache back-end.
    */
   protected function setupMemoryCache() {
-    $this->memoryCache = $this->memoryCache ?: new MemoryBackend();
+    $this->memoryCache = $this->memoryCache ?: new MemoryBackend(new PhpSerialize());
 
     $this->cacheFactory->expects($this->atLeastOnce())
       ->method('get')