Retrieves a System.Web.UI.SkinBuilder instance for the specified control, which is used to apply a theme and control skin in a designer environment.
A System.Web.UI.SkinBuilder instance, if one is defined for the specified control type; otherwise, null.
The ThemeProvider.GetSkinBuilder(Control) method is called by the System.Web.UI.ControlBuilder base class to apply a theme and any control skin to a control when it is built at design time.