bug:自己赋值给自己

layout/admin/scrollBar.vue

@@ -29,7 +29,7 @@ export default {
         this.top = Math.min(0, this.top + eventDelta);
       } else if ($containerHeight - delta < $wrapperHeight) {
         if (this.top < -($wrapperHeight - $containerHeight + delta)) {
-          this.top = this.top;
+          // this.top = this.top;
         } else {
           this.top = Math.max(this.top + eventDelta, $containerHeight - $wrapperHeight - delta);
         }