Returns the underlying GtkCellArea which might be @cell_layout if called on a GtkCellArea or might be %NULL if no GtkCellArea is used by @cell_layout.
the cell area used by @cell_layout
See Implementation
Returns the underlying GtkCellArea which might be @cell_layout if called on a GtkCellArea or might be %NULL if no GtkCellArea is used by @cell_layout.