Fix error when jsonifying certain oauth errors
Fix error when jsonifying certain oauth errors

pferreir/indico,ThiefMaster/indico,pferreir/indico,pferreir/indico,DirkHoffmann/indico,pferreir/indico,DirkHoffmann/indico,ThiefMaster/indico,indico/indico,indico/indico,ThiefMaster/indico,DirkHoffmann/indico,DirkHoffmann/indico,ThiefMaster/indico,indico/indico,indico/indico