Changed check_access() to use the same user reference to retrieve per…

…missions as used earlier in the method to check authentication

Using the context for the later check can break under certain conditions

sitetree/sitetreeapp.py

@@ -918,7 +918,7 @@ def check_access(self, item: 'TreeItemBase', context: Context) -> bool:
             user_perms = self._current_user_permissions
 
             if user_perms is _UNSET:
-                user_perms = self.get_permissions(context['user'], item)
+                user_perms = self.get_permissions(self.current_request.user, item)
                 self._current_user_permissions = user_perms
 
             if item.access_perm_type == MODEL_TREE_ITEM_CLASS.PERM_TYPE_ALL: