123322: Avoid logging overhead for (root) transactions with only one participant
Transactions with only 1 participant (or resource) will resort to 1-phase commit and there is no way to recover their state. Therefore, logging adds useless overhead and is now avoided.
123291: Unexpected XAException errorCode during 2PC commit: call recover() to find out if retry makes sense
We now try to avoid unnecessary and annoying HeuristicHazard outcomes and dito retries, by doing extra checks in the XAResource backend whenever possible.