diff --git a/core/modules/toolbar/toolbar.module b/core/modules/toolbar/toolbar.module
index 2deab72..a8cdff0 100644
--- a/core/modules/toolbar/toolbar.module
+++ b/core/modules/toolbar/toolbar.module
@@ -206,7 +206,7 @@ function ($object) {
   }
 
   // Get toolbar items from all modules that implement hook_toolbar().
-  $items = \Drupal::moduleHandler()->invokeAll('toolbar', $langcode);
+  $items = \Drupal::moduleHandler()->invokeAll('toolbar', array($langcode));
   // Allow for altering of hook_toolbar().
   \Drupal::moduleHandler()->alter('toolbar', $items, $langcode);
   // Sort the children.