builddependencies: consider all divergent successors
We were only considering one. In test-evolve-abort-conentdiv.t:165,
the input revs were {5, 8} and dependency dict was {8: set([]), 5:
set([10])}, which is a little weird (10 is not in the input set). It
still worked because the callers used it (they seemed to only care if
there were *any* dependencies).
This patch fixes the issue by considering all successors. That means
the dependency dict will be {8: set([]), 5: set([8, 10])} after this
patch. The next patch will remove the 10 from that set.
#!/bin/sh
sleep 5
echo "new desc" >> $1