diff -u b/core/modules/user/src/AdministratorRoleSettingsForm.php b/core/modules/user/src/AdministratorRoleSettingsForm.php
--- b/core/modules/user/src/AdministratorRoleSettingsForm.php
+++ b/core/modules/user/src/AdministratorRoleSettingsForm.php
@@ -1,124 +1,117 @@
 <?php
 
-/**
- * @file
- * Contains \Drupal\user\AdministratorRoleSettingsForm.
- */
-
 namespace Drupal\user;
 
 use Drupal\Core\Form\ConfigFormBase;
 use Drupal\Core\Config\ConfigFactoryInterface;
-use Drupal\Core\Extension\ModuleHandler;
 use Drupal\Core\Form\FormStateInterface;
-use Drupal\Core\Render\Element;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
 /**
- * Contribute form.
+ * Configure administrator role settings for this site.
  */
-class AdministratorRoleSettingsForm extends ConfigFormBase
-{
-
-    public function __construct(ConfigFactoryInterface $config_factory, ModuleHandler $module_handler, RoleStorageInterface $role_storage)
-    {
-        parent::__construct($config_factory);
-        $this->moduleHandler = $module_handler;
-        $this->roleStorage = $role_storage;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public static function create(ContainerInterface $container)
-    {
-        return new static(
-            $container->get('config.factory'),
-            $container->get('module_handler'),
-            $container->get('entity.manager')->getStorage('user_role')
-        );
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getFormId()
-    {
-        return 'administrator_role_settings';
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function getEditableConfigNames()
-    {
-        return [
-        'system.site',
-        'user.mail',
-        'user.settings',
-        ];
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function buildForm(array $form, FormStateInterface $form_state)
-    {
-        $form = parent::buildForm($form, $form_state);
-        $config = $this->config('user.settings');
-        $mail_config = $this->config('user.mail');
-        $site_config = $this->config('system.site');
-        // Administrative role option.
-        $form['admin_role'] = [
-        '#type' => 'details',
-        '#title' => $this->t('Administrator role'),
-        '#open' => true,
-        ];
-        // Do not allow users to set the anonymous or authenticated user roles as the
-        // administrator role.
-        $roles = user_role_names(true);
-        unset($roles[RoleInterface::AUTHENTICATED_ID]);
-
-        $admin_roles = $this->roleStorage->getQuery()
-            ->condition('is_admin', true)
-            ->execute();
-        $default_value = reset($admin_roles);
-
-        $form['admin_role']['user_admin_role'] = [
-        '#type' => 'select',
-        '#title' => $this->t('Administrator role'),
-        '#empty_value' => '',
-        '#default_value' => $default_value,
-        '#options' => $roles,
-        '#description' => $this->t('This role will be automatically assigned new permissions whenever a module is enabled. Changing this setting will not affect existing permissions.'),
-        // Don't allow to select a single admin role in case multiple roles got
-        // marked as admin role already.
-        '#access' => count($admin_roles) <= 1,
-        ];
-        return parent::buildForm($form, $form_state);
-    }
+class AdministratorRoleSettingsForm extends ConfigFormBase {
 
-    /**
-     * {@inheritdoc}
-     */
-    public function submitForm(array &$form, FormStateInterface $form_state)
-    {
-        $saved_role = $form_state->getValue('user_admin_role');
-        if ($form_state->hasValue('user_admin_role')) {
-            $admin_roles = $this->roleStorage->getQuery()
-                ->condition('is_admin', true)
-                ->execute();
-
-            foreach ($admin_roles as $rid) {
-                $this->roleStorage->load($rid)->setIsAdmin(false)->save();
-            }
-
-            $new_admin_role = $form_state->getValue('user_admin_role');
-            if ($new_admin_role) {
-                $this->roleStorage->load($new_admin_role)->setIsAdmin(true)->save();
-            }
-        }
-        parent::submitForm($form, $form_state);
+  /**
+   * The role storage used when changing the admin role.
+   *
+   * @var \Drupal\user\RoleStorageInterface
+   */
+  protected $roleStorage;
+
+  /**
+   * Constructs a \Drupal\user\AdministratorRoleSettingsForm object.
+   *
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
+   *   The factory for configuration objects.
+   * @param \Drupal\user\RoleStorageInterface $role_storage
+   *   The role storage.
+   */
+  public function __construct(ConfigFactoryInterface $config_factory, RoleStorageInterface $role_storage) {
+    parent::__construct($config_factory);
+    $this->roleStorage = $role_storage;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container) {
+    return new static(
+      $container->get('config.factory'),
+      $container->get('entity.manager')->getStorage('user_role')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormId() {
+    return 'administrator_role_settings';
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function getEditableConfigNames() {
+    return [
+      'system.site',
+      'user.mail',
+      'user.settings',
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    $form = parent::buildForm($form, $form_state);
+
+    // Administrative role option.
+    $form['admin_role'] = [
+      '#type' => 'details',
+      '#title' => $this->t('Administrator role'),
+      '#open' => TRUE,
+    ];
+    // Do not allow users to set the anonymous or authenticated user roles as
+    // the administrator role.
+    $roles = user_role_names(TRUE);
+    unset($roles[RoleInterface::AUTHENTICATED_ID]);
+    $admin_roles = $this->roleStorage->getQuery()
+      ->condition('is_admin', TRUE)
+      ->execute();
+    $default_value = reset($admin_roles);
+    $form['admin_role']['user_admin_role'] = [
+      '#type' => 'select',
+      '#title' => $this->t('Administrator role'),
+      '#empty_value' => '',
+      '#default_value' => $default_value,
+      '#options' => $roles,
+      '#description' => $this->t('This role will be automatically assigned new permissions whenever a module is enabled. Changing this setting will not affect existing permissions.'),
+      // Don't allow to select a single admin role in case multiple roles got
+      // marked as admin role already.
+      '#access' => count($admin_roles) <= 1,
+    ];
+
+    return parent::buildForm($form, $form_state);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function submitForm(array &$form, FormStateInterface $form_state) {
+    if ($form_state->hasValue('user_admin_role')) {
+      $admin_roles = $this->roleStorage->getQuery()
+        ->condition('is_admin', TRUE)
+        ->execute();
+      foreach ($admin_roles as $rid) {
+        $this->roleStorage->load($rid)->setIsAdmin(FALSE)->save();
+      }
+      $new_admin_role = $form_state->getValue('user_admin_role');
+      if ($new_admin_role) {
+        $this->roleStorage->load($new_admin_role)->setIsAdmin(TRUE)->save();
+      }
     }
+    parent::submitForm($form, $form_state);
+  }
 
 }