fix v-if component root test in Firefox
fix v-if component root test in Firefox

hanhongyuan/vue,wushuyi/vue,Jinjiang/vue,xueyaodeai/vue,leemotive/vue,pramudaprakash/GITHUB,leemotive/vue,KingMario/vue,Hanks10100/vue,greennyreborn/vue,Kingwl/vue,leemotive/vue,lizhiyao/vue,pramudaprakash/GITHUB,xueyaodeai/vue,pramudaprakash/GITHUB,Hanks10100/vue,lizhiyao/vue,posva/vue,hanhongyuan/vue,vuejs/vue,Jinjiang/vue,KingMario/vue,gebilaoxiong/vue,sreesirisha/GITMidtermexam,Kingwl/vue,cnchanning/vue,sreesirisha/GITMidtermexam,leemotive/vue,optimizely/vue,wushuyi/vue,sreesirisha/GITMidtermexam,xueyaodeai/vue,hanhongyuan/vue,Ddder-FE/vue,Hanks10100/vue,posva/vue,lizhiyao/vue,posva/vue,Kingwl/vue,KingMario/vue,Hanks10100/vue,cnchanning/vue,posva/vue,cnchanning/vue,xueyaodeai/vue,sreesirisha/GITMidtermexam,Jinjiang/vue,pramudaprakash/GITHUB,Jinjiang/vue,Ddder-FE/vue,vuejs/vue,Ddder-FE/vue,greennyreborn/vue,gebilaoxiong/vue,lizhiyao/vue,KingMario/vue,Ddder-FE/vue,greennyreborn/vue,greennyreborn/vue,hanhongyuan/vue,vuejs/vue,gebilaoxiong/vue,Kingwl/vue,vuejs/vue