gtkd , addondraw is deprecated

[Mike Wey]

On 21-05-2021 12:35, Alain De Vos wrote:
> What is the advised function to use instead of 
> gtk.Widget.Widget.addOnDraw ?
> ```
> this()
>          { addOnDraw(&drawCallback);}
> ```

Change the `Context` passed to the drawCallback to a `Scoped!Context` 
only the non scoped overload is deprecated.

```
bool drawCallback(Scoped!Context cr, Widget widget)
```

-- 
Mike Wey