AnimateInstance RTE when using IEffect.filter in a transition

Steps to reproduce:
1. Compile and run this simplified application:

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark">

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

<s:transitions>
<s:Transition>
<s:Move filter="add" targets="

"/>
</s:Transition>
</s:transitions>

<s:controlBarContent>
<s:Button label="change state" click="currentState=currentState=='state1'?'state2':'state1'"/>
</s:controlBarContent>

<s:Button id="b2" label="Label" width="100" height="100"
includeIn="state2" x.state1="50" x.state2="0" />

</s:Application>

2. Click change state

Actual Results:

RTE:

ReferenceError: Error #1074: Illegal write to read-only property parent on spark.components.Button.
at spark.effects.supportClasses::AnimateInstance/setValue()[E:\dev\4.y\frameworks\projects\spark\src\spark\effects\supportClasses\AnimateInstance.as:1116]
at spark.effects.supportClasses::AnimateTransformInstance/applyValues()[E:\dev\4.y\frameworks\projects\spark\src\spark\effects\supportClasses\AnimateTransformInstance.as:772]
at spark.effects.supportClasses::AnimateInstance/animationUpdate()[E:\dev\4.y\frameworks\projects\spark\src\spark\effects\supportClasses\AnimateInstance.as:760]
at spark.effects.animation::Animation/sendUpdateEvent()[E:\dev\4.y\frameworks\projects\spark\src\spark\effects\animation\Animation.as:841]
at spark.effects.animation::Animation/start()[E:\dev\4.y\frameworks\projects\spark\src\spark\effects\animation\Animation.as:1397]
at spark.effects.animation::Animation/play()[E:\dev\4.y\frameworks\projects\spark\src\spark\effects\animation\Animation.as:1088]
at spark.effects.supportClasses::AnimateInstance/play()[E:\dev\4.y\frameworks\projects\spark\src\spark\effects\supportClasses\AnimateInstance.as:558]
at spark.effects.supportClasses::AnimateTransformInstance/play()[E:\dev\4.y\frameworks\projects\spark\src\spark\effects\supportClasses\AnimateTransformInstance.as:624]
at spark.effects.supportClasses::AnimateInstance/startEffect()[E:\dev\4.y\frameworks\projects\spark\src\spark\effects\supportClasses\AnimateInstance.as:433]
at spark.effects.supportClasses::AnimateTransformInstance/startEffect()[E:\dev\4.y\frameworks\projects\spark\src\spark\effects\supportClasses\AnimateTransformInstance.as:251]
at mx.effects::Effect/play()[E:\dev\4.y\frameworks\projects\framework\src\mx\effects\Effect.as:1246]
at mx.core::UIComponent/commitCurrentState()[E:\dev\4.y\frameworks\projects\framework\src\mx\core\UIComponent.as:10515]
at mx.core::UIComponent/setCurrentState()[E:\dev\4.y\frameworks\projects\framework\src\mx\core\UIComponent.as:10322]
at mx.core::UIComponent/set currentState()[E:\dev\4.y\frameworks\projects\framework\src\mx\core\UIComponent.as:6425]
at states/___states_Button1_click()[/Users/stshongr/workspaces/325268/statesdemo/src/states.mxml:17]

Expected Results:

No RTE, move effect should play.

Workaround (if any):

Don't use IEffect.filter