[spark_skins] Size of Spark skinned Halo CheckBox is different from FxCheckBox without label

Steps to reproduce:
1. Compile & run:
<?xml version="1.0" encoding="utf-8"?>
<FxApplication xmlns="http://ns.adobe.com/mxml/2009" >
<layout>
<VerticalLayout/>
</layout>
<Script>
<![CDATA[
[Bindable]
[Embed(source="disabledIcon.gif")]
public var digif:Class;

]]
>
</Script>

<CheckBox id="cb" />
<FxCheckBox id="fxcb" />
<Label text="Halo CheckBox height:

width:

"/>
<Label text="Gumbo CheckBox height:

width:

"/>
</FxApplication>

Actual Results:
Halo CheckBox w/ Spark Skin's dimensions are: 11x13
FxCheckBox dimensions are: 13x18
(Halo CheckBox w/ Halo theme is 18x14)

Expected Results:
Halo CheckBox w/ Spark Skin's dimensions should be the same as FxCheckBox, 13x18
FxCheckBox dimensions are: 13x18

Workaround (if any):
Add an empty label (label=" ").