Revert "Fix window minimization."
Revert "Fix window minimization."

This reverts commit 20ddbad2adf97e93765cbe89f6532a9b945242e2.

It didn't work with owned windows, there's something else going on here.

SuperJMN/Avalonia,SuperJMN/Avalonia,AvaloniaUI/Avalonia,AvaloniaUI/Avalonia,AvaloniaUI/Avalonia,SuperJMN/Avalonia,SuperJMN/Avalonia,SuperJMN/Avalonia,SuperJMN/Avalonia,AvaloniaUI/Avalonia,SuperJMN/Avalonia,AvaloniaUI/Avalonia,AvaloniaUI/Avalonia,AvaloniaUI/Avalonia