
When a transition is set up with a delay, it may be removed before it
actually started. We won't get a ::stopped signal in that case, with
the result that we currently end up with a mismatched unredirection
disabling.
Address this by only disable unredirection once the transition has
actually started.
https://gitlab.gnome.org/GNOME/gnome-shell/issues/1788
(cherry picked from commit 38ad1d7c13
)