7181986: NMT ON: Assertion failure when running jdi ExpiredRequestDeletionTest Summary: Changed _query_lock to heap object from static object. Also fixed _query_lock and snapshot lock ranks, so they can participate deadlock detection. Reviewed-by: coleenp, dholmes, kvn

^build/
^dist/
^drop/
^drop_included/
^webrev/
/nbproject/private/
^.hgtip
.DS_Store