fix editing variable no not use group

sample/workdir/subtree1.json

@@ -1,5 +1,11 @@
 {
+  "version": "1.8.0",
   "name": "subtree1",
+  "desc": "子树1",
+  "firstid": 1,
+  "group": [],
+  "import": [],
+  "declvar": [],
   "root": {
     "id": 1,
     "name": "Sequence",
@@ -20,10 +26,5 @@
         }
       }
     ]
-  },
-  "desc": "子树1",
-  "firstid": 1,
-  "group": [],
-  "import": [],
-  "declvar": []
+  }
 }