XARecoveryModuleHelpersUnitTest hang

The test checks that recovery helpers can be removed at the correct stages during recovery scans. The CI job http://albany.eng.hst.ams2.redhat.com/job/narayana-codeCoverage/196 shows the hang.

The junit test thread:

• starts 2 threads that will remove a recovery helper
• triggers xaRecoveryModule.periodicWorkFirstPass()
• triggers xaRecoveryModule.periodicWorkSecondPass()
• joins with remover threads

The jstack output shows:

• the two threads in the process of removing a recovery helper and are waiting for the first pass to finish;
• the junit test thread is waiting to join with these two threads;

Since both recovery passes must have completed it looks like the remover threads weren't notified when the first pass completed.