The test does a clutter_actor_set_scale_full() call that only updates
the scale center (i.e. no changes to scale-x/y), but expects to receive
notifications of actor scale changes.
Since "Revert "Revert "ClutterActor: Optimize away idempotent
scale/position updates"" these are optimized away, so just drop the
assumption.
Since commit 5cb5baa7d4, we skip transitions when updating an
actor's scale/position to the existing value. As a result, we
don't get change notification on those properties either - given
that the properties did not actually change, that behavior seems
fine, so just modify the test to not expect a notify signal for
unchanged properties.
