[polly] Unbreak buildbot.

The test failed since commit
bc10888dc "DomTree: Make PostDomTree indifferent to block successors swap"
which is a re-commit of
c35585e20 "DomTree: Make PostDomTree immune to block successors swap"

GitOrigin-RevId: 1139d899d58916a0662c76e1847b3b12c5a4a5dc
1 file changed