fix a race condition where db sent the end of a response to a cxn before the db thread used cxn-allocated data to stop its query
fix a race condition where db sent the end of a response to a cxn before the db thread used cxn-allocated data to stop its query

rhansen/rpstir,rhansen/rpstir,rhansen/rpstir,rhansen/rpstir,rhansen/rpstir