ENG-10444: Added comment warning about this class not being thread-safe.
ENG-10444: Added comment warning about this class not being thread-safe.

simonzhangsm/voltdb,paulmartel/voltdb,deerwalk/voltdb,VoltDB/voltdb,deerwalk/voltdb,VoltDB/voltdb,paulmartel/voltdb,simonzhangsm/voltdb,paulmartel/voltdb,migue/voltdb,migue/voltdb,deerwalk/voltdb,paulmartel/voltdb,paulmartel/voltdb,simonzhangsm/voltdb,migue/voltdb,deerwalk/voltdb,VoltDB/voltdb,simonzhangsm/voltdb,paulmartel/voltdb,paulmartel/voltdb,simonzhangsm/voltdb,migue/voltdb,deerwalk/voltdb,VoltDB/voltdb,simonzhangsm/voltdb,deerwalk/voltdb,paulmartel/voltdb,VoltDB/voltdb,simonzhangsm/voltdb,deerwalk/voltdb,simonzhangsm/voltdb,migue/voltdb,migue/voltdb,VoltDB/voltdb,VoltDB/voltdb,deerwalk/voltdb,migue/voltdb,migue/voltdb