Add test for the 404 handler. r=fabrice
Add test for the 404 handler. r=fabrice

julienw/foxbox,hkoka/foxbox,gabrielesvelto/foxbox,mcav/foxbox,hkoka/foxbox,aosmond/foxbox,gabrielesvelto/foxbox,Yoric/foxbox,fabricedesre/foxbox,Yoric/foxbox,fxbox/foxbox,fxbox/foxbox,hkoka/foxbox,fxbox/foxbox,aosmond/foxbox,fabricedesre/foxbox,npark-mozilla/foxbox,Yoric/foxbox,fxbox/foxbox,mcav/foxbox,mcav/foxbox,cr/foxbox,aosmond/foxbox,npark-mozilla/foxbox,cr/foxbox,hkoka/foxbox,npark-mozilla/foxbox,npark-mozilla/foxbox,julienw/foxbox,gabrielesvelto/foxbox,julienw/foxbox,fabricedesre/foxbox,mcav/foxbox,cr/foxbox,fabricedesre/foxbox,cr/foxbox,Yoric/foxbox