Masking element on RIchText should inherit the target group's coordinate space

Steps to reproduce:
1. Compile the bugfile with the following RichText graphic:
<RichText x="50" fontFamily="Myriad Pro" fontSize="15" width="195">
<content> The quick brown fox jumped over the lazy dog. <p fontFamily="Myriad Pro">And that is where the story normally ends. The reality is that the dog was a decoy and the fox jumped straight into a trap and then was promptly shot by the dog's owner and cooked up for dinner.</p> The End. </content>
<mask>
<Group blendMode="normal">
<Ellipse x="50" width="95" height="150">
<fill>
<SolidColor/>
</fill>
</Ellipse>
</Group>
</mask>
</RichText>

Actual Results: The RichText element is placed at (50,0) on the stage. The mask is also placed at (50.0) on the stage.

Expected Results: The mask should get the coordinate space of its parent group as if its a child. Therefore, on the stage, the mask should be at (100,0)

Workaround (if any):