Informs the cell renderer that the editing is stopped.
If canceled is true, the cell renderer will emit the `GtkCellRenderer`
editing_canceled signal.
This function should be called by cell renderer implementations in response to the `GtkCellEditable:GtkCellRenderer:editing-done
` signal of `GtkCellEditable`.
| this |
A `GtkCellRenderer` |
| canceled |
true if the editing has been canceled |