taken from field
When specified, the shape will cause the region to be
rendered as the specified shape rather than as a rounded rectangle.
When null, the Region is rendered as a rounded rectangle. When rendered
as a Shape, any Background is used to fill the shape, although any
background insets are ignored as are background radii. Any BorderStrokes
defined are used for stroking the shape. Any BorderImages are ignored.
@default null
@css shape SVG shape string
Diagram: Parent