diff --git a/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitGdTest.php b/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitGdTest.php
index ac84f71..654f1b5 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitGdTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitGdTest.php
@@ -8,7 +8,6 @@
 namespace Drupal\system\Tests\Image;
 
 use Drupal\simpletest\DrupalUnitTestBase;
-use Drupal\Core\ImageToolkit\ImageToolkitManager;
 
 /**
  * Test the core GD image manipulation functions.
@@ -215,7 +214,7 @@ function testManipulations() {
       );
     }
 
-    $manager = new ImageToolkitManager($this->container->get('container.namespaces'), $this->container->get('cache.cache'), $this->container->get('language_manager'));
+    $manager = $this->container->get('plugin.manager.image_toolkit');
     foreach ($files as $file) {
       foreach ($operations as $op => $values) {
         // Load up a fresh image.
diff --git a/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitTest.php b/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitTest.php
index c765d2f..37e1c7f 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitTest.php
@@ -7,8 +7,6 @@
 
 namespace Drupal\system\Tests\Image;
 
-use Drupal\Core\ImageToolkit\ImageToolkitManager;
-
 /**
  * Test that the functions in image.inc correctly pass data to the toolkit.
  */
@@ -26,7 +24,7 @@ public static function getInfo() {
    * available toolkits.
    */
   function testGetAvailableToolkits() {
-    $manager = new ImageToolkitManager($this->container->get('container.namespaces'), $this->container->get('cache.cache'), $this->container->get('language_manager'));
+    $manager = $this->container->get('plugin.manager.image_toolkit');
     $toolkits = $manager->getAvailableToolkits();
     $this->assertTrue(isset($toolkits['test']), 'The working toolkit was returned.');
     $this->assertFalse(isset($toolkits['broken']), 'The toolkit marked unavailable was not returned');
diff --git a/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitTestBase.php b/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitTestBase.php
index 503bf0e..ae59ed4 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitTestBase.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Image/ToolkitTestBase.php
@@ -8,8 +8,6 @@
 namespace Drupal\system\Tests\Image;
 
 use Drupal\simpletest\WebTestBase;
-use Drupal\Core\ImageToolkit\ImageToolkitManager;
-use stdClass;
 
 /**
  * Base class for image manipulation testing.
@@ -31,7 +29,7 @@ function setUp() {
     parent::setUp();
 
     // Use the image_test.module's test toolkit.
-    $manager = new ImageToolkitManager($this->container->get('container.namespaces'), $this->container->get('cache.cache'), $this->container->get('language_manager'));
+    $manager = $this->container->get('plugin.manager.image_toolkit');
     $this->toolkit = $manager->createInstance('test');
 
     // Pick a file for testing.
@@ -40,7 +38,7 @@ function setUp() {
 
     // Setup a dummy image to work with, this replicate image_load() so we
     // can avoid calling it.
-    $this->image = new stdClass();
+    $this->image = new \stdClass();
     $this->image->source = $this->file;
     $this->image->info = image_get_info($this->file);
     $this->image->toolkit = $this->toolkit;