Returns a paintable that has the given intrinsic size and draws nothing.
This is often useful for implementing the
GdkPaintableInterface.get_current_image virtual function when the paintable is in an
incomplete state (like a [class@Gtk.MediaStream] before receiving the first frame).
The intrinsic width to report. Can be 0 for no width.
The intrinsic height to report. Can be 0 for no height.