@Override
    public Procedure[] execute(TestProcEnv env) {
      if (env.toggleKillBeforeStoreUpdate) {
        ProcedureTestingUtility.toggleKillBeforeStoreUpdate(procExecutor);
      }
      if (env.toggleKillAfterStoreUpdate) {
        ProcedureTestingUtility.toggleKillAfterStoreUpdate(procExecutor);
      }
      return new Procedure[] { new TestChildProcedure(), new TestChildProcedure() };
    }
Test the state setting that happens after store to WAL; in particular the bit where we set the
parent runnable again after its children have all completed successfully. See HBASE-20978.
hbase-procedure/src/test/java/org/apache/hadoop/hbase/procedure2/TestChildProcedures.java