[useragent] handle error when result in null
[useragent] handle error when result in null

luto/ShareJS,matthewbauer/ShareJS,igmcdowell/ShareJS,freewind/ShareJS,igmcdowell/ShareJS,rasata/ShareJS,a0x/ShareJS,gdseller/ShareJS,erpframework/ShareJS,share/ShareJS,modulexcite/ShareJS,gdseller/ShareJS,Nzaga/ShareJS,mcanthony/ShareJS,kustomzone/ShareJS