diff --git a/core/modules/config/src/Tests/DefaultConfigTest.php b/core/modules/config/src/Tests/DefaultConfigTest.php
index 4880561..254502a 100644
--- a/core/modules/config/src/Tests/DefaultConfigTest.php
+++ b/core/modules/config/src/Tests/DefaultConfigTest.php
@@ -38,7 +38,8 @@ public function testDefaultConfig() {
       \Drupal::service('config.storage'),
       new TestInstallStorage(InstallStorage::CONFIG_SCHEMA_DIRECTORY),
       \Drupal::service('cache.discovery'),
-      \Drupal::service('module_handler')
+      \Drupal::service('module_handler'),
+      \Drupal::service('event_dispatcher')
     );
 
     // Create a configuration storage with access to default configuration in
diff --git a/core/modules/system/src/Tests/Plugin/PluginTestBase.php b/core/modules/system/src/Tests/Plugin/PluginTestBase.php
index 8cf95a7..1f852a0 100644
--- a/core/modules/system/src/Tests/Plugin/PluginTestBase.php
+++ b/core/modules/system/src/Tests/Plugin/PluginTestBase.php
@@ -14,6 +14,7 @@
 use Drupal\plugin_test\Plugin\DefaultsTestPluginManager;
 use Drupal\Core\Cache\MemoryBackend;
 use Drupal\Core\Extension\ModuleHandler;
+use Symfony\Component\EventDispatcher\EventDispatcher;
 
 /**
  * Base class for Plugin API unit tests.
@@ -48,7 +49,8 @@ public function setUp() {
     $this->testPluginManager = new TestPluginManager();
     $this->mockBlockManager = new MockBlockManager();
     $module_handler = new ModuleHandler(array(), new MemoryBackend('plugin'));
-    $this->defaultsTestPluginManager = new DefaultsTestPluginManager($module_handler);
+    $event_dispatcher = new EventDispatcher();
+    $this->defaultsTestPluginManager = new DefaultsTestPluginManager($module_handler, $event_dispatcher);
 
     // The expected plugin definitions within each manager. Several tests assert
     // that these plugins and their definitions are found and returned by the