5e6aee6367
We just made an half assed attempt to wait, but e.g. when clients were waiting for a frame event, the attempt was not enough, as the clients would not ack any configure until the time they were scheduled to paint again. Fix this by actually tracking newly pending configurations, and waiting for them to return. On X11, still be lazy and hope for the best, as there is no similar configuration tracking there. Some tests were updated to use just 'wait' when there was no actual need for any extra waiting. Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3701>