Update masking behavior: configure the mask to be the lesser of the maximum size and the actual SWF frame size in each dimensions.
Update masking behavior: configure the mask to be the lesser of
the maximum size and the actual SWF frame size in each dimensions.

This may break some avatars that were smaller than full size but
drawing a little outside their bounds to the right or bottom. Probably
nobody was actually depending on this bug..


git-svn-id: b675b909355d5cf946977f44a8ec5a6ceb3782e4@265 ed5b42cb-e716-0410-a449-f6a68f950b19

threerings/nenya,threerings/nenya