Transform GdkQuartzMonitor geometry to Gdk coordinate system.
Move computation of Display geometry from GdkQuartzScreen to
GdkQuartzDisplay and use AppKit coordinates.
Closes https://gitlab.gnome.org/GNOME/gtk/issues/1593
Moving the initialization of the GdkQuartzMonitors to GdkQuartzDisplay from
the now-obsolete GdkQuartzScreen. Use QuartzDisplayServices for
monitor enumeration and to populate the GdkMonitor properties. This is
better aligned with acting on the Quartz Services callbacks for monitor
changes and with Cairo which also uses CoreGraphics for drawing.
