Fix save state generation on dynamic created objects. (#3537)

* fix statefull on new group

src/mixins/stateful.mixin.js

@@ -67,6 +67,9 @@
     saveState: function(options) {
       var propertySet = options && options.propertySet || originalSet,
           destination = '_' + propertySet;
+      if (!this[destination]) {
+        return this.setupState(options);
+      }
       saveProps(this, destination, this[propertySet]);
       if (options && options.stateProperties) {
         saveProps(this, destination, options.stateProperties);