Steps to reproduce:

var api = new mw.Api(), repoApi = new wb.api.RepoApi( api );
repoApi.getEntities( 'Q4115189' );

requests the URL https://www.wikidata.org/w/api.php?action=wbgetentities&format=json&ids=Q4115189&dir=ascending
which answers with

{"warnings":{"main":{"*":"Unrecognized parameter: 'dir'"}}, ...

Expected result: The parameter dir should only set when recognized.