delete duplicated logic.

Author: Edwin Betancourt

packages/switch/src/component.vue

@@ -117,9 +117,7 @@
     },
     watch: {
       checked() {
-        if (this.$refs.input) {
-          this.$refs.input.checked = this.checked;
-        }
+        this.$refs.input.checked = this.checked;
         if (this.activeColor || this.inactiveColor) {
           this.setBackgroundColor();
         }
@@ -136,7 +134,6 @@
         this.$nextTick(() => {
           // set input's checked property
           // in case parent refuses to change component's value
-          this.$refs.input.checked = this.checked;
           if (this.$refs.input) {
             this.$refs.input.checked = this.checked;
           }