diff --git a/core/modules/system/lib/Drupal/system/Controller/ThemeController.php b/core/modules/system/lib/Drupal/system/Controller/ThemeController.php
new file mode 100644
index 0000000..e28e20d
--- /dev/null
+++ b/core/modules/system/lib/Drupal/system/Controller/ThemeController.php
@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * @file
+ * Definition of \Drupal\system\Controller\ThemeController.
+ */
+
+namespace Drupal\system\Controller;
+
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;
+/**
+ * Controller for theme handling.
+ */
+class ThemeController {
+
+  /**
+   * Disables a theme.
+   */
+  function disable(Request $request) {
+    $theme = $request->get('theme');
+    $token = $request->get('token');
+    if (isset($theme) && isset($token) && drupal_valid_token($token, 'system-theme-operation-link')) {
+      // Get current list of themes.
+      $themes = list_themes();
+
+      // Check if the specified theme is one recognized by the system.
+      if (!empty($themes[$theme])) {
+        // Do not disable the default or admin theme.
+        if ($theme === config('system.theme')->get('default') || $theme === config('system.theme')->get('admin')) {
+          drupal_set_message(t('%theme is the default theme and cannot be disabled.', array('%theme' => $themes[$theme]->info['name'])), 'error');
+        }
+        else {
+          theme_disable(array($theme));
+          drupal_set_message(t('The %theme theme has been disabled.', array('%theme' => $themes[$theme]->info['name'])));
+        }
+      }
+      else {
+        drupal_set_message(t('The %theme theme was not found.', array('%theme' => $theme)), 'error');
+      }
+      drupal_goto('admin/appearance');
+    }
+    throw new AccessDeniedHttpException();
+  }
+}