To easily implement custom styles more "flat", a new Skin (global) style property themeIsFlat could be useful to tell the skin to not draw some elements like: borders around components, no gradients, no shadows.
By default this is false, so the original behaviour is not changed.
Check later if makes sense to add an additional property (but in any component) to let him override this global setting (but at the moment I don't think it would be so useful).
Original proposal here: http://apache-pivot-developers.417237.n3.nabble.com/New-style-attribute-for-do-not-draw-border-in-components-for-2-1-td4026771.html
and some discussion here: