Parses uri_ref according to flags and, if it is a
relative URI, resolves it relative to
base_uri_string. If the result is not a valid absolute URI, it will be
discarded, and an error returned.
(If base_uri_string is null, this just returns uri_ref, or
null if uri_ref is invalid or not absolute.)
Parses uri_ref according to flags and, if it is a relative URI, resolves it relative to base_uri_string. If the result is not a valid absolute URI, it will be discarded, and an error returned.
(If base_uri_string is null, this just returns uri_ref, or null if uri_ref is invalid or not absolute.)