Fix Contribution.getLogInfo
Fix Contribution.getLogInfo

Failed if an abstract field contained just a plain string instead of an
AbstractFieldContent object

pferreir/indico,indico/indico,indico/indico,indico/indico,pferreir/indico,mvidalgarcia/indico,DirkHoffmann/indico,ThiefMaster/indico,DirkHoffmann/indico,mvidalgarcia/indico,DirkHoffmann/indico,mic4ael/indico,pferreir/indico,ThiefMaster/indico,OmeGak/indico,mic4ael/indico,mvidalgarcia/indico,pferreir/indico,OmeGak/indico,indico/indico,ThiefMaster/indico,mic4ael/indico,mic4ael/indico,ThiefMaster/indico,OmeGak/indico,DirkHoffmann/indico,mvidalgarcia/indico,OmeGak/indico