Returns the underlying gtk.CellArea which might be cell_layout if called on a gtk.CellArea or might be NULL if no gtk.CellArea is used by cell_layout.
the cell area used by cell_layout, or NULL in case no cell area is used.
3.0
Returns the underlying gtk.CellArea which might be cell_layout if called on a gtk.CellArea or might be NULL if no gtk.CellArea is used by cell_layout.