diff --git a/core/modules/image/src/Tests/ImageAdminStylesTest.php b/core/modules/image/src/Tests/ImageAdminStylesTest.php
index d998883..5487078 100644
--- a/core/modules/image/src/Tests/ImageAdminStylesTest.php
+++ b/core/modules/image/src/Tests/ImageAdminStylesTest.php
@@ -124,6 +124,12 @@ function testStyle() {
 
     // Load the saved image style.
     $style = entity_load('image_style', $style_name);
+
+    // Ensure that third party settings were added to the config entity.
+    // These are added by a hook_image_style_presave() implemented in
+    // image_module_test module.
+    $this->assertEqual('bar', $style->getThirdPartySetting('image_module_test', 'foo'), 'Third party settings were added to the image style.');
+
     // Ensure that the image style URI matches our expected path.
     $style_uri_path = $style->url();
     $this->assertTrue(strpos($style_uri_path, $style_path) !== FALSE, 'The image style URI is correct.');
diff --git a/core/modules/image/src/Tests/ImageFieldTestBase.php b/core/modules/image/src/Tests/ImageFieldTestBase.php
index 561737a..64b912e 100644
--- a/core/modules/image/src/Tests/ImageFieldTestBase.php
+++ b/core/modules/image/src/Tests/ImageFieldTestBase.php
@@ -32,7 +32,7 @@
    *
    * @var array
    */
-  public static $modules = array('node', 'image', 'field_ui');
+  public static $modules = array('node', 'image', 'field_ui', 'image_module_test');
 
   protected $admin_user;
 
diff --git a/core/modules/image/tests/modules/image_module_test/config/schema/image_module_test.schema.yml b/core/modules/image/tests/modules/image_module_test/config/schema/image_module_test.schema.yml
new file mode 100644
index 0000000..a36719d
--- /dev/null
+++ b/core/modules/image/tests/modules/image_module_test/config/schema/image_module_test.schema.yml
@@ -0,0 +1,7 @@
+image_style.third_party.image_module_test:
+  type: mapping
+  label: 'Schema for image_module_test module additions to image_style entity'
+  mapping:
+    foo:
+      type: string
+      label: 'Label for foo'
diff --git a/core/modules/image/tests/modules/image_module_test/image_module_test.module b/core/modules/image/tests/modules/image_module_test/image_module_test.module
index 0242f1e..df71375 100644
--- a/core/modules/image/tests/modules/image_module_test/image_module_test.module
+++ b/core/modules/image/tests/modules/image_module_test/image_module_test.module
@@ -5,6 +5,8 @@
  * Provides Image module hook implementations for testing purposes.
  */
 
+use Drupal\image\ImageStyleInterface;
+
 function image_module_test_file_download($uri) {
   $default_uri = \Drupal::state()->get('image.test_file_download') ?: FALSE;
   if ($default_uri == $uri) {
@@ -21,3 +23,12 @@ function image_module_test_image_effect_info_alter(&$effects) {
   $image_effects_definition_called = &drupal_static(__FUNCTION__, 0);
   $image_effects_definition_called++;
 }
+
+/**
+ * Implements hook_image_style_presave().
+ *
+ * Used to save test third party settings in the image style entity.
+ */
+function image_module_test_image_style_presave(ImageStyleInterface $style) {
+  $style->setThirdPartySetting('image_module_test', 'foo', 'bar');
+}