4e1747e6ec
Since commit 551e8278416, we don't always pass a callback parameter. However passing it on as undefined to ibus doesn't work, as gjs doesn't accept that as a valid callback value and throw an error. As a result, we can end up with no layout selected in the keyboard menu and an "empty" indicator. Fix this by explicitly passing null if no callback has been provided. https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/293 (cherry picked from commit 74bb9e62492bacda372904d30891eb97685e9b0c)