FindBugs: Fix NPE in XStream2#findConverter() when class parameter is null
FindBugs: Fix NPE in XStream2#findConverter() when class parameter is null

damianszczepanik/jenkins,godfath3r/jenkins,ajshastri/jenkins,ndeloof/jenkins,Jochen-A-Fuerbacher/jenkins,kohsuke/hudson,MarkEWaite/jenkins,tfennelly/jenkins,DanielWeber/jenkins,bpzhang/jenkins,batmat/jenkins,damianszczepanik/jenkins,wuwen5/jenkins,stephenc/jenkins,tangkun75/jenkins,tfennelly/jenkins,jenkinsci/jenkins,v1v/jenkins,ikedam/jenkins,patbos/jenkins,ikedam/jenkins,amuniz/jenkins,v1v/jenkins,godfath3r/jenkins,DanielWeber/jenkins,MarkEWaite/jenkins,wuwen5/jenkins,tangkun75/jenkins,lilyJi/jenkins,lilyJi/jenkins,MarkEWaite/jenkins,daniel-beck/jenkins,v1v/jenkins,bkmeneguello/jenkins,lilyJi/jenkins,rsandell/jenkins,batmat/jenkins,azweb76/jenkins,ndeloof/jenkins,tangkun75/jenkins,kohsuke/hudson,ErikVerheul/jenkins,wuwen5/jenkins,Jimilian/jenkins,MarkEWaite/jenkins,patbos/jenkins,hplatou/jenkins,damianszczepanik/jenkins,tfennelly/jenkins,dariver/jenkins,recena/jenkins,Vlatombe/jenkins,aldaris/jenkins,stephenc/jenkins,bkmeneguello/jenkins,batmat/jenkins,dariver/jenkins,Vlatombe/jenkins,tfennelly/jenkins,viqueen/jenkins,ErikVerheul/jenkins,ikedam/jenkins,Ykus/jenkins,v1v/jenkins,amuniz/jenkins,DanielWeber/jenkins,wuwen5/jenkins,oleg-nenashev/jenkins,jenkinsci/jenkins,lilyJi/jenkins,rsandell/jenkins,oleg-nenashev/jenkins,stephenc/jenkins,dariver/jenkins,sathiya-mit/jenkins,godfath3r/jenkins,andresrc/jenkins,escoem/jenkins,ikedam/jenkins,rsandell/jenkins,ajshastri/jenkins,azweb76/jenkins,hplatou/jenkins,batmat/jenkins,patbos/jenkins,Jochen-A-Fuerbacher/jenkins,ErikVerheul/jenkins,fbelzunc/jenkins,patbos/jenkins,oleg-nenashev/jenkins,kohsuke/hudson,recena/jenkins,oleg-nenashev/jenkins,aldaris/jenkins,Vlatombe/jenkins,tangkun75/jenkins,bpzhang/jenkins,Ykus/jenkins,wuwen5/jenkins,Vlatombe/jenkins,batmat/jenkins,escoem/jenkins,damianszczepanik/jenkins,sathiya-mit/jenkins,Jochen-A-Fuerbacher/jenkins,daniel-beck/jenkins,DanielWeber/jenkins,stephenc/jenkins,daniel-beck/jenkins,bkmeneguello/jenkins,amuniz/jenkins,Jimilian/jenkins,Ykus/jenkins,rsandell/jenkins,tfennelly/jenkins,daniel-beck/jenkins,Jochen-A-Fuerbacher/jenkins,Jimilian/jenkins,recena/jenkins,batmat/jenkins,tfennelly/jenkins,escoem/jenkins,recena/jenkins,jenkinsci/jenkins,viqueen/jenkins,sathiya-mit/jenkins,daniel-beck/jenkins,MarkEWaite/jenkins,Jimilian/jenkins,rsandell/jenkins,aldaris/jenkins,Jimilian/jenkins,ikedam/jenkins,damianszczepanik/jenkins,fbelzunc/jenkins,azweb76/jenkins,Vlatombe/jenkins,aldaris/jenkins,Jochen-A-Fuerbacher/jenkins,azweb76/jenkins,hplatou/jenkins,sathiya-mit/jenkins,pjanouse/jenkins,MarkEWaite/jenkins,ikedam/jenkins,bkmeneguello/jenkins,bpzhang/jenkins,DanielWeber/jenkins,ajshastri/jenkins,sathiya-mit/jenkins,lilyJi/jenkins,ndeloof/jenkins,ErikVerheul/jenkins,ajshastri/jenkins,daniel-beck/jenkins,ajshastri/jenkins,viqueen/jenkins,bpzhang/jenkins,daniel-beck/jenkins,ikedam/jenkins,viqueen/jenkins,sathiya-mit/jenkins,jenkinsci/jenkins,rsandell/jenkins,Vlatombe/jenkins,kohsuke/hudson,ikedam/jenkins,escoem/jenkins,andresrc/jenkins,Ykus/jenkins,jenkinsci/jenkins,ErikVerheul/jenkins,pjanouse/jenkins,Ykus/jenkins,fbelzunc/jenkins,pjanouse/jenkins,godfath3r/jenkins,wuwen5/jenkins,dariver/jenkins,ndeloof/jenkins,tangkun75/jenkins,escoem/jenkins,jenkinsci/jenkins,batmat/jenkins,daniel-beck/jenkins,fbelzunc/jenkins,bkmeneguello/jenkins,amuniz/jenkins,hplatou/jenkins,ErikVerheul/jenkins,andresrc/jenkins,kohsuke/hudson,hplatou/jenkins,lilyJi/jenkins,andresrc/jenkins,ajshastri/jenkins,ndeloof/jenkins,ErikVerheul/jenkins,recena/jenkins,Ykus/jenkins,viqueen/jenkins,Vlatombe/jenkins,kohsuke/hudson,hplatou/jenkins,aldaris/jenkins,hplatou/jenkins,aldaris/jenkins,tfennelly/jenkins,bkmeneguello/jenkins,ndeloof/jenkins,fbelzunc/jenkins,DanielWeber/jenkins,andresrc/jenkins,v1v/jenkins,pjanouse/jenkins,oleg-nenashev/jenkins,azweb76/jenkins,bpzhang/jenkins,patbos/jenkins,bkmeneguello/jenkins,sathiya-mit/jenkins,recena/jenkins,dariver/jenkins,recena/jenkins,v1v/jenkins,damianszczepanik/jenkins,stephenc/jenkins,damianszczepanik/jenkins,escoem/jenkins,lilyJi/jenkins,pjanouse/jenkins,amuniz/jenkins,andresrc/jenkins,azweb76/jenkins,jenkinsci/jenkins,Jimilian/jenkins,wuwen5/jenkins,DanielWeber/jenkins,rsandell/jenkins,viqueen/jenkins,MarkEWaite/jenkins,rsandell/jenkins,bpzhang/jenkins,amuniz/jenkins,stephenc/jenkins,dariver/jenkins,patbos/jenkins,tangkun75/jenkins,patbos/jenkins,azweb76/jenkins,Ykus/jenkins,oleg-nenashev/jenkins,pjanouse/jenkins,ajshastri/jenkins,stephenc/jenkins,oleg-nenashev/jenkins,ndeloof/jenkins,bpzhang/jenkins,kohsuke/hudson,jenkinsci/jenkins,escoem/jenkins,godfath3r/jenkins,fbelzunc/jenkins,godfath3r/jenkins,aldaris/jenkins,viqueen/jenkins,dariver/jenkins,Jimilian/jenkins,amuniz/jenkins,damianszczepanik/jenkins,andresrc/jenkins,Jochen-A-Fuerbacher/jenkins,kohsuke/hudson,pjanouse/jenkins,tangkun75/jenkins,Jochen-A-Fuerbacher/jenkins,godfath3r/jenkins,v1v/jenkins,MarkEWaite/jenkins,fbelzunc/jenkins