[代码完善](v2.5): v2.5 beta 修复用户管理左侧部门搜索问题

2.5 Beta 详情：https://www.ydyno.com/archives/1225.html

src/views/system/user/index.vue

@@ -390,7 +390,9 @@ export default {
       const sort = 'id,desc'
       const params = { sort: sort }
       if (typeof node !== 'object') {
-        params['name'] = node
+        if (node) {
+          params['name'] = node
+        }
       } else if (node.level !== 0) {
         params['pid'] = node.data.id
       }