addResult = function(ids) {
            if (ids) {
                if (ids.indexOf(' ') > 0) {
                    result = result.concat(attrib.value.split(' '));
                } else {
                    result.push(ids);
                }
            }
        }
Gets a list of all IDs this element references in either ARIA or HTML attributes.

@param {Element} element The element to check for idref attributes.
@returns {Array.<string>} Any IDs this element references.