diff --git a/core/modules/language/tests/language_elements_test/language_elements_test.module b/core/modules/language/tests/language_elements_test/language_elements_test.module
deleted file mode 100644
index a85b7f3..0000000
--- a/core/modules/language/tests/language_elements_test/language_elements_test.module
+++ /dev/null
@@ -1,41 +0,0 @@
-<?php
-
-/**
- * @file
- * Mock module for language form elements test.
- */
-
-/**
- * A form containing a language configuration element.
- */
-function language_elements_configuration_element() {
-  $conf = language_get_default_configuration('some_custom_type', 'some_bundle');
-
-  $form['lang_configuration'] = array(
-    '#type' => 'language_configuration',
-    '#entity_information' => array(
-      'entity_type' => 'some_custom_type',
-      'bundle' => 'some_bundle',
-    ),
-    '#default_value' => $conf,
-  );
-
-  $form['submit'] = array(
-    '#type' => 'submit',
-    '#value' => 'Save',
-  );
-  $form['#submit'][] = 'language_configuration_element_submit';
-  return $form;
-}
-
-/**
- * A form containing a language select element.
- */
-function language_elements_configuration_element_test() {
-  $form['langcode'] = array(
-    '#title' => t('Language select'),
-    '#type' => 'language_select',
-    '#default_value' => language_get_default_langcode('custom_type', 'some_bundle'),
-  );
-  return $form;
-}
diff --git a/core/modules/language/tests/language_elements_test/language_elements_test.routing.yml b/core/modules/language/tests/language_elements_test/language_elements_test.routing.yml
index 5a5698c..168bfbe 100644
--- a/core/modules/language/tests/language_elements_test/language_elements_test.routing.yml
+++ b/core/modules/language/tests/language_elements_test/language_elements_test.routing.yml
@@ -1,7 +1,7 @@
 language_elements_test.config_element:
   path: '/language-tests/language_configuration_element'
   defaults:
-    _content: '\Drupal\language_elements_test\Form\LanguageElementsTestForm::configFormElement'
+    _form: '\Drupal\language_elements_test\Form\LanguageConfigurationElement'
     _title: 'Language configuration form element'
   requirements:
     _access: 'TRUE'
@@ -9,7 +9,7 @@ language_elements_test.config_element:
 language_elements_test.config_element_test:
   path: '/language-tests/language_configuration_element_test'
   defaults:
-    _content: '\Drupal\language_elements_test\Form\LanguageElementsTestForm::configFormElementTest'
+    _form: '\Drupal\language_elements_test\Form\LanguageConfigurationElementTest'
     _title: 'Language configuration form element'
   requirements:
     _access: 'TRUE'
diff --git a/core/modules/language/tests/language_elements_test/src/Form/LanguageConfigurationElement.php b/core/modules/language/tests/language_elements_test/src/Form/LanguageConfigurationElement.php
new file mode 100644
index 0000000..58d2d0d
--- /dev/null
+++ b/core/modules/language/tests/language_elements_test/src/Form/LanguageConfigurationElement.php
@@ -0,0 +1,51 @@
+<?php
+/**
+ * @file
+ * Contains \Drupal\language_elements_test\Form\LanguageConfigurationElement.
+ */
+
+namespace Drupal\language_elements_test\Form;
+
+use Drupal\Core\Form\FormBase;
+
+/**
+ * A form containing a language configuration element.
+ */
+class LanguageConfigurationElement extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormID() {
+    return 'language_elements_configuration_element';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, array &$form_state, $pid = NULL) {
+    $conf = language_get_default_configuration('some_custom_type', 'some_bundle');
+
+    $form['lang_configuration'] = array(
+      '#type' => 'language_configuration',
+      '#entity_information' => array(
+        'entity_type' => 'some_custom_type',
+        'bundle' => 'some_bundle',
+      ),
+      '#default_value' => $conf,
+    );
+
+    $form['submit'] = array(
+      '#type' => 'submit',
+      '#value' => 'Save',
+    );
+    $form['#submit'][] = 'language_configuration_element_submit';
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, array &$form_state) {
+  }
+}
diff --git a/core/modules/language/tests/language_elements_test/src/Form/LanguageConfigurationElementTest.php b/core/modules/language/tests/language_elements_test/src/Form/LanguageConfigurationElementTest.php
new file mode 100644
index 0000000..274c56b
--- /dev/null
+++ b/core/modules/language/tests/language_elements_test/src/Form/LanguageConfigurationElementTest.php
@@ -0,0 +1,40 @@
+<?php
+/**
+ * @file
+ * Contains \Drupal\language_elements_test\Form\LanguageConfigurationElementTest.
+ */
+
+namespace Drupal\language_elements_test\Form;
+
+use Drupal\Core\Form\FormBase;
+
+/**
+ * A form containing a language select element.
+ */
+class LanguageConfigurationElementTest extends FormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormID() {
+    return 'language_elements_configuration_element_test';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, array &$form_state, $pid = NULL) {
+    $form['langcode'] = array(
+      '#title' => t('Language select'),
+      '#type' => 'language_select',
+      '#default_value' => language_get_default_langcode('custom_type', 'some_bundle'),
+    );
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, array &$form_state) {
+  }
+}
diff --git a/core/modules/language/tests/language_elements_test/src/Form/LanguageElementsTestForm.php b/core/modules/language/tests/language_elements_test/src/Form/LanguageElementsTestForm.php
deleted file mode 100644
index 010b472..0000000
--- a/core/modules/language/tests/language_elements_test/src/Form/LanguageElementsTestForm.php
+++ /dev/null
@@ -1,34 +0,0 @@
-<?php
-
-/**
- * @file
- * Contains \Drupal\language_elements_test\Form\LanguageElementsTestForm.
- */
-
-namespace Drupal\language_elements_test\Form;
-
-/**
- * Controller routines for language_elements_test routes.
- */
-class LanguageElementsTestForm {
-
-  /**
-   * Wraps language_elements_configuration_element().
-   *
-   * @todo Remove language_elements_configuration_element().
-   */
-  public function configFormElement() {
-    return \Drupal::formBuilder()->getForm('language_elements_configuration_element');
-  }
-
-  /**
-   * Wraps language_element_tests_configuration_element_test().
-   *
-   * @todo Remove language_element_tests_configuration_element_test().
-   */
-  public function configFormElementTest() {
-    return \Drupal::formBuilder()->getForm('language_elements_configuration_element_test');
-  }
-
-}
-