[Wayland] Add a mechanism for accissibility tools to obtain window corordinates
Feature summary
Accessibility tools such as Orca and the GNOME shell magnifier need a mechanism to obtain the coordinates of a window on the screen. Under X this was possible via ATK but with the move to Wayland this method only reports cursor coordinates relative to the window.
This is necessary to allow magnification tools to track the text/focus cursor.
How would you like it to work
Ideally there would be a method of granting an accessibility tool permission to request a windows absolute position.
I'd be interested in helping with this, however I'd need some pointers as I have so far failed to build gnome shell from source.