gdkseat: Provide way to ungrab single device

Submitted by Pavel Grunt

Description

Hi,

I was trying to move from deprecated gdk_pointer_ungrab() and gdk_keyboard_ungrab() to gdkseat functions. Sometimes I need to grab both keyboard and pointer and ungrab them separately. Hovewer I noticed that there is just gdk_seat_ungrab() ungrabbing everything and there is no (not deprecated) way for ungrabbing only the keyboard or the pointer.

Is it expected to call gdk_seat_ungrab() followed by gdk_seat_grab() ?

In my case the code changed from: gdk_pointer_ungrab()

to: gdk_seat_ungrab() if keyboard should be grabbed: // this check may not be trivial gdk_seat_grab()

Version: 3.22.x