Medium: PE: Bug N:385265 - The failure stickiness of group children is ignored until it reaches -INFINITY
This applies to all but the first child of the group.
The fix (when a constraint's score is INFINITY) is to update only the nodes that _dont_ satisfy the
constraint and set their score to -INFINITY. Thus leaving only the allowed node and with its original
score.

Mercurial revision: 8f364a8102fdd3cc08066072f4e1dc0e7563ade8