When manipulating the allocation of a ClutterActor from an allocate()
vfunc override, clutter_actor_set_allocation() is used to let Clutter
know about the changes.
If the actors allocation or its absolute origin did not change before
that, this can also affect the actors absolute_origin_changed property
used by the children to detect changes to their absolute position.
So fix this bug (which luckily didn't seem to affect us so far) and set
priv->absolute_origin_changed to TRUE in case the origin changes inside
clutter_actor_set_allocation_internal(). Since this function is always
called when our allocation changes, we no longer need to update
absolute_origin_changed in clutter_actor_allocate() now.
Since a change to the absolute origin always affects the resource scale,
too, we also need to move that check from clutter_actor_allocate() here
to make sure we update the resource scale.
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1247