Configures padding to edges surrounding a Scrollable when the Textfield scrolls into view.
When this widget receives focus and is not completely visible (for example scrolled partially off the screen or overlapped by the keyboard) then it will attempt to make itself visible by scrolling a surrounding Scrollable, if one is present. This value controls how far from the edges of a Scrollable the TextField will be positioned after the scroll.
Defaults to EdgeInsets.all(20.0).
final EdgeInsets scrollPadding