.first() can only be used on ordered results

Trying to do .first() on a not ordered ResultSet would result on an
UnorderedError, so get .any(), since it's the fallback.

Fixes: http://bugs.async.com.br/show_bug.cgi?id=5422
Change-Id: I5e252abaa0fbe12446298e14ef3c4de3ae41bb19