fix: active window fixes

[mayakwd]

Description

This is a follow-up for the previous _NET_ACTIVE_WINDOW clear PR.

During thorough investigation of the issue regarding mouse-look lock in the games connected to Xwayland and Wine (Proton), I found out that the implementation is not quite aligned with X server behavior.

So what exactly X server does when focus move from a window to None or PointerRoot:

• it sends to the window losing focus FocusOut with NotifyDetail::NONLINEAR/INFERIOR (and NONLINEAR_VIRTUAL to the ancestors), and never send NotifyDetail::NONE to a non-root window.
• it sends FocusIn with NotifyDetail::NONE or NotifyDetail::POINTER_ROOT to the root, meaning the clearing of the _NET_ACTIVE_WINDOW

The other focus-tracking issues I found and fixed:

• When focus becomes POINTER_ROOT, the server sends NotifyDetail::POINTER to the window under pointer, which is not an activation. Thus FocusIn with NotifyDetail::POINTER is now ignored.
• FocusIn with NotifyMode::GRAB/UNGRAB is now ignored - keyboard grab redirects keys without changing the actual focus. Meaning that previous behavior did the following _NET_ACTIVE_WINDOW changes: "app" -> "menu" -> "app".

Checklist

• I agree to smithay's Developer Certificate of Origin.

[Drakulix]

Makes sense. Thanks!

[Drakulix]

Can you rebase? 506fda0 should've fixed CI