GEODE-3249 fix has been pushed to release/1.2.1

[Bruce Schuchardt]

I've cherry-picked the fix on release/1.2.1

commit 0b881b515eb1dcea974f0f5c1b40da03d42af9cf
Author: Bruce Schuchardt <bschucha...@pivotal.io>
Date:   Fri Sep 8 09:35:18 2017 -0700

    GEODE-3249 Validate internal client/server messages