Fix a typo.

Change-Id: Ia163b95ca73a79b6acfe8c9a362f15b1f32eba63
Reviewed-on: http://review.couchbase.org/34273
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>