MB-10181: disabled autocomplete for secure fields

Change-Id: I9d4c40aff149e9526d69fc16d6fc725ff4e89357
Reviewed-on: http://review.couchbase.org/33530
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>