* Properly wipe the thumbnail canvas before handing it to the app for
its contents to be drawn
* Provide a getView() method in DragThumbnailBuilder that allows
clients or subclasses to get at the associated view. This is
especially for clients that want to draw entire (sub)layouts as
the drag thumbnail, by overriding onDrawThumbnail(Canvas c)
like this:
// Override specifically for drawing a whole ViewGroup into
// the drag thumbnail canvas
@Override
public void onDrawThumbnail(Canvas c) {
getView().dispatchDraw(c);
}
Change-Id: Ib43ddd7cf1d44faf2d7f6ba79f102bc3c7f14596