Simplify uniqueList

lib/utils/common.js

@@ -97,15 +97,7 @@ class common extends utils {
    * @returns {Array}
    */
   static uniqueList (list) {
-    let tmp = {}
-    let r = []
-    for (let i = 0; i < list.length; i++) {
-      tmp[list[i]] = list[i]
-    }
-    for (let i in tmp) {
-      r.push(tmp[i])
-    }
-    return r
+    return list.filter((v, i, a) => a.indexOf(v) === i)
   }
 
   /**