A GraphicElement that isn't included in the currentState still has a non-null displayObject value

Steps to reproduce:
1. Compile and run:

<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark">

<s:controlBarContent>
<s:Button label="1. go to state2" click="currentState='state2'" />
<s:Button label="2. go to state1" click="currentState='state1'" />
<s:Button label="3. check value of stage" click="trace(g.displayObject == null, 'expecting true')" />
</s:controlBarContent>

<s:states>
<s:State name="state1" />
<s:State name="state2" />
</s:states>

<s:HGroup>
<s:Rect id="g" width="50" height="50" includeIn="state2">
<s:fill><s:SolidColor color="red" /></s:fill>
</s:Rect>
</s:HGroup>

</s:Application>

2. Click button 1
3. Click button 2
4. Click button 3

Actual Results:

Trace output: false expecting true

Expected Results:

Trace output: true expecting true

Workaround (if any):