Fix NOTIFICATION_WM_CLOSE_REQUEST in Embedded Floating Window

[Hilderin]

• Fixes Closing game running in editor no longer sends NotificationWMCloseRequest - v4.4Beta1 #101863

This PR should fixes the notification NOTIFICATION_WM_CLOSE_REQUEST when closing the floating window.

I changed the way the embedded process is closed. In the previous implementation, I based the code on the stop button in the editor which kills the process. Now, I use a native send message in Windows and Linux the close the game window.

I added to rework the WindowWrapper to prevent to closing of the floating window while the game is closing. That's why I added the WindowWrapper::set_override_close_request method.

I did not changed the editor stop button, it's working as before. It kills the process, preventing the notification.

Tested on Windows 11 and Ubuntu 23.10.

[bruvzg]

Seems to be working as expected.

Note: if the process is taking a long time to process this notification, it will cause editor to fully lock-up until it's done or killed externally, but this seems to be an issue with embedded mode in general,

[Hilderin]

Oh, good point. I think this could be avoided if I pass a timeout in the SendMessage on Window. I'll try later.

EDITED: Nevermind, I already use a PostMessage which does not wait. The problem is probably that the procress is locked and cannot process windows message. Indeed it's actually a global issue.

[Repiteo]

Thanks!