H5：零元商品也可以购买

htmldev/dashboard/src/views/sell/shopcart/shopcart.vue

@@ -166,7 +166,7 @@ export default {
       return count
     },
     payClass () {
-      if (this.totalPrice < 1) {
+      if (this.totalCount < 1) {
         return 'not-enough'
       } else {
         return 'enough'
@@ -299,7 +299,7 @@ export default {
       })
     },
     pay () {
-      if (this.totalPrice < 1) {
+      if (this.totalCount < 1) {
         return
       }
       this.$store.commit('shopcart/UPDATE_SELECTFOODS', this.selectFoods)