The repair for the inflated cumulative records deleted the suspect rows,
committed, and then re-ran the detector. When the detector failed, which
a timeout on a large account or a restart can cause, the records stayed
deleted, and since discovery looks for the suspect rows the account was
never repaired again (#1031).
The delete and the re-derivation now run in one transaction, with the
detector reading through it, so they commit together or not at all. The
transaction gets five minutes; the detector took 19.8 s on the largest
seeded account.
