box: re-set max extents sizes to -1 during recalc
box: re-set max extents sizes to -1 during recalc

0 is a "valid" max size, so using it as the default value
results in a box being 0x0 if there are no explicit max size
hints set on any child objects

ref aef9d23550bbcd74829a5d75d5226ba394a9da87

tasn/elementary,tasn/elementary,tasn/elementary,rvandegrift/elementary,rvandegrift/elementary,tasn/elementary,rvandegrift/elementary,rvandegrift/elementary,tasn/elementary