Force the animation timebase for ATL in show layer.

We really should be propagating the transform state, but there
isn't really a good way to do that at the moment. (It isn't clear
where we'd store the old state.)

This is a reasonable, if ugly, workaround.

See: http://lemmasoft.renai.us/forums/ucp.php?i=pm&mode=view&f=0&p=147158