Disable failing assertion

Change-Id: I7c2a1c6e4595f30bffc452ead9a17aafdfed0f39
Reviewed-on: http://review.couchbase.org/27928
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>