compiler codegen improvement (#5024)
compiler codegen improvement (#5024)

* remove unnecessary code

* improve compiler codegen

* change false to 0

Kingwl/vue,vuejs/vue,xueyaodeai/vue,KingMario/vue,cnchanning/vue,KingMario/vue,Ddder-FE/vue,Jinjiang/vue,lizhiyao/vue,vuejs/vue,xueyaodeai/vue,KingMario/vue,Kingwl/vue,vuejs/vue,Kingwl/vue,Ddder-FE/vue,Hanks10100/vue,Jinjiang/vue,vuejs/vue,KingMario/vue,Jinjiang/vue,Ddder-FE/vue,Hanks10100/vue,Jinjiang/vue,xueyaodeai/vue,Ddder-FE/vue,lizhiyao/vue,lizhiyao/vue,Hanks10100/vue,optimizely/vue,Hanks10100/vue,lizhiyao/vue,Kingwl/vue,cnchanning/vue,cnchanning/vue,xueyaodeai/vue