Spark button skin is overly conservative about hiding it's label if the button is too narrow

Steps to reproduce:
1. Run this:

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

<s:Button width="25" label="X"/>
<mx:Button y="50" width="25" label="X"/>

</s:Application>

Actual Results:
Spark Button doesn't show it's label, but MX does.

Expected Results:
C'mon, there's plenty of room there to show "X"! Seriously though, this is fairly annoying because a little "X" button is the easiest way to prototype a "close" button.

Workaround (if any):
Reskin the Button and lower the left and right constraints on the "labelDisplay" component.