
In some situations we could end up not with lingering 'view-loaded'
handler. This could result in delayed spring animate-in being initiated,
e.g. after a minute after the activities overview was already closed.
Fix this by removing any lingering signal or later handlers when
unmapping.
Fixes: 5c33fe4a0a
https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1155