oddbconv: fix unexpected panic thrown from (*MapKeyPath).FromMap
oddbconv: fix unexpected panic thrown from (*MapKeyPath).FromMap

rickmak/skygear-server,rickmak/skygear-server,SkygearIO/skygear-server,SkygearIO/skygear-server,rickmak/skygear-server,SkygearIO/skygear-server,SkygearIO/skygear-server