Fix bug http://bugs.adobe.com/jira/browse/SDK-17267 Setting scale to non-integer values causes the sides of Gumbo Button to disappear
The problem is that when the scale is less than 1, the pixels occupied by the border rectangle are also occupied by the fill rectangle and the fill rectangle renders on top of the border one. The fix switches the order in the skins.
QE Notes: Affects the visuals of any FxButton at pixel (1,1) slightly due to antialiasing.
Doc Notes: None
tests: checkintests, Mustella (Button)