diff --git a/core/lib/Drupal/Core/Theme/Registry.php b/core/lib/Drupal/Core/Theme/Registry.php
index 784abd3..c7149be 100644
--- a/core/lib/Drupal/Core/Theme/Registry.php
+++ b/core/lib/Drupal/Core/Theme/Registry.php
@@ -160,7 +160,7 @@ class Registry implements DestructableInterface {
    * @param $theme_handler
    *   The theme handler.
    */
-  public function __construct($root, CacheBackendInterface $cache, LockBackendInterface $lock, ModuleHandlerInterface $module_handler, $theme_name = NULL, ThemeHandlerInterface $theme_handler) {
+  public function __construct($root, CacheBackendInterface $cache, LockBackendInterface $lock, ModuleHandlerInterface $module_handler, ThemeHandlerInterface $theme_handler, $theme_name = NULL) {
     $this->root = $root;
     $this->cache = $cache;
     $this->lock = $lock;