Error in _votingapi_query() method

Line adding 'function' criteria is missing last 'is_string' parameter, as 'function' is a string criteria ('average', 'sum', count'):

_votingapi_query_builder('function', $criteria['function'], $query, $args);

it should be:

_votingapi_query_builder('function', $criteria['function'], $query, $args, TRUE);