Fixing FlushTest and warmup.

Change-Id: I6598491eedc348a2edfe50caa074d62a41d31c8f
Reviewed-on: http://review.couchbase.org/28878
Tested-by: Michael Nitschinger <michael.nitschinger@couchbase.com>
Reviewed-by: Matt Ingenthron <matt@couchbase.com>