The new_mongos_old_mongod_wire_version_clash.js test expects the last-stable version of mongo servers to issue an older wire version. But since we upgrade the wire protocol version independently of the server version, this assumption isn't always true.

The test should be modified to backtrack binary versions until it finds one that uses an older wire protocol version.

The test should also be unblacklisted as part of this ticket or SERVER-35169, whichever one happens first.