"gdk_screen_get_monitor_geometry" and "gdk_screen_get_monitor_workarea" are still used in "PlatformScreenGtk.cpp" but they are deprecated since GTK 3.22.
I'm uploading a patch to this.
Created attachment 371835 [details]
Created attachment 371836 [details]
Comment on attachment 371836 [details]
Clearing flags on attachment: 371836
Committed r246310: <https://trac.webkit.org/changeset/246310>
All reviewed patches have been landed. Closing bug.