Issue #2230921 by nod_: Regression: 'Back to site' button forgets last...

Issue #2230921 by nod_: Regression: 'Back to site' button forgets last non-admin page after visiting 'block region demo'.

core/modules/block/lib/Drupal/block/Controller/BlockController.php

@@ -36,7 +36,7 @@ public function demo($theme) {
             // page by path_is_admin() function in order to use the frontend
             // theme. Since JavaScript relies on a proper separation of admin
             // pages, it needs to know this is an actual administrative page.
-            'data' => array('currentPathIsAdmin' => TRUE),
+            'data' => array('path' => array('currentPathIsAdmin' => TRUE)),
             'type' => 'setting',
           )
         ),