If they set attributedString to nil twice, ignore the second one.
If they set attributedString to nil twice, ignore the second one.

aaronschubert0/AsyncDisplayKit,eanagel/AsyncDisplayKit,maicki/AsyncDisplayKit,lappp9/AsyncDisplayKit,levi/AsyncDisplayKit,marmelroy/AsyncDisplayKit,facebook/AsyncDisplayKit,JetZou/AsyncDisplayKit,tomizimobile/AsyncDisplayKit,nrcmedia/AsyncDisplayKit,gazreese/AsyncDisplayKit,tomizimobile/AsyncDisplayKit,marmelroy/AsyncDisplayKit,facebook/AsyncDisplayKit,smyrgl/AsyncDisplayKit,flovouin/AsyncDisplayKit,nrcmedia/AsyncDisplayKit,tomizimobile/AsyncDisplayKit,gazreese/AsyncDisplayKit,jellenbogen/AsyncDisplayKit,rahul-malik/AsyncDisplayKit,Adlai-Holler/AsyncDisplayKit,maicki/AsyncDisplayKit,yufenglv/AsyncDisplayKit,Xinchi/AsyncDisplayKit,george-gw/AsyncDisplayKit,Xinchi/AsyncDisplayKit,rcancro/AsyncDisplayKit,Adlai-Holler/AsyncDisplayKit,flovouin/AsyncDisplayKit,tomizimobile/AsyncDisplayKit,yufenglv/AsyncDisplayKit,rmls/AsyncDisplayKit,nrcmedia/AsyncDisplayKit,smyrgl/AsyncDisplayKit,garrettmoon/AsyncDisplayKit,aaronschubert0/AsyncDisplayKit,harryworld/AsyncDisplayKit,yufenglv/AsyncDisplayKit,garrettmoon/AsyncDisplayKit,smyrgl/AsyncDisplayKit,maicki/AsyncDisplayKit,rmls/AsyncDisplayKit,hannahmbanana/AsyncDisplayKit,hannahmbanana/AsyncDisplayKit,romyilano/AsyncDisplayKit,george-gw/AsyncDisplayKit,romyilano/AsyncDisplayKit,lappp9/AsyncDisplayKit,samhsiung/AsyncDisplayKit,nrcmedia/AsyncDisplayKit,harryworld/AsyncDisplayKit,levi/AsyncDisplayKit,flovouin/AsyncDisplayKit,hannahmbanana/AsyncDisplayKit,eanagel/AsyncDisplayKit,JetZou/AsyncDisplayKit,maicki/AsyncDisplayKit,hannahmbanana/AsyncDisplayKit,rcancro/AsyncDisplayKit,garrettmoon/AsyncDisplayKit,Adlai-Holler/AsyncDisplayKit,rcancro/AsyncDisplayKit,chrisdanford/AsyncDisplayKit,aaronschubert0/AsyncDisplayKit,rahul-malik/AsyncDisplayKit,eanagel/AsyncDisplayKit,bimawa/AsyncDisplayKit,gazreese/AsyncDisplayKit,aaronschubert0/AsyncDisplayKit,harryworld/AsyncDisplayKit,jellenbogen/AsyncDisplayKit,rahul-malik/AsyncDisplayKit,harryworld/AsyncDisplayKit,JetZou/AsyncDisplayKit,eanagel/AsyncDisplayKit,rmls/AsyncDisplayKit,rcancro/AsyncDisplayKit,rmls/AsyncDisplayKit,marmelroy/AsyncDisplayKit,Adlai-Holler/AsyncDisplayKit,smyrgl/AsyncDisplayKit,flovouin/AsyncDisplayKit,Adlai-Holler/AsyncDisplayKit,Xinchi/AsyncDisplayKit,jellenbogen/AsyncDisplayKit,JetZou/AsyncDisplayKit,nrcmedia/AsyncDisplayKit,samhsiung/AsyncDisplayKit,lappp9/AsyncDisplayKit,JetZou/AsyncDisplayKit,gazreese/AsyncDisplayKit,bimawa/AsyncDisplayKit,facebook/AsyncDisplayKit,facebook/AsyncDisplayKit,yufenglv/AsyncDisplayKit,jellenbogen/AsyncDisplayKit,harryworld/AsyncDisplayKit,eanagel/AsyncDisplayKit,rahul-malik/AsyncDisplayKit,hannahmbanana/AsyncDisplayKit,jellenbogen/AsyncDisplayKit,chrisdanford/AsyncDisplayKit,Xinchi/AsyncDisplayKit,chrisdanford/AsyncDisplayKit,samhsiung/AsyncDisplayKit,george-gw/AsyncDisplayKit,flovouin/AsyncDisplayKit,samhsiung/AsyncDisplayKit,aaronschubert0/AsyncDisplayKit,tomizimobile/AsyncDisplayKit,george-gw/AsyncDisplayKit,garrettmoon/AsyncDisplayKit,garrettmoon/AsyncDisplayKit,maicki/AsyncDisplayKit,rcancro/AsyncDisplayKit,chrisdanford/AsyncDisplayKit,bimawa/AsyncDisplayKit,levi/AsyncDisplayKit,rmls/AsyncDisplayKit,bimawa/AsyncDisplayKit,marmelroy/AsyncDisplayKit,romyilano/AsyncDisplayKit,Xinchi/AsyncDisplayKit,romyilano/AsyncDisplayKit,levi/AsyncDisplayKit,levi/AsyncDisplayKit,yufenglv/AsyncDisplayKit,lappp9/AsyncDisplayKit