SERVER-13435 do not run dropdb_race.js in smalloplog

(cherry picked from commit cffd39b33fd0c6e311237cacc7360da3ea776a21)
SERVER-13431 _me should not reference mmapped memory

(cherry picked from commit 54123be0d616307b946122194586bd3cf93d2c3b)
Merge remote-tracking branch 'upstream/v2.6' into v2.6