[Vala] [vala 0.8.0] construct properties in interface

[Nicolas Joseph <gege2061 redaction-developpez com>]

Hello,

I have a compilation error with vala 0.8.0:

public interface Valide.Plugin : Object
> {
>   public abstract string path { get; construct set; }
>   public abstract Window window { get; construct set; }
> }

libvalide/plugin.vala:30.38-30.51: error: construct properties not supported
> for specified property type
> libvalide/plugin.vala:35.40-35.53: error: construct properties not
> supported for specified property type

What is the good way to fix this error?

-- 
Nicolas Joseph