demo from ’Object Change Detection‘ doesn't work (#661)
demo from ’Object Change Detection‘ doesn't work (#661)

vm.$set(this.userProfile, 'age', 27)    ==>   vm.$set(vm.userProfile, 'age', 27);
vuejs/jp.vuejs.org,vuejs/jp.vuejs.org,potato4d/jp.vuejs.org,potato4d/jp.vuejs.org