This change was made downstream in WebKit:
https://bugs.webkit.org/show_bug.cgi?id=218303

It turns out we must use EAGL in macCatalyst on Apple Silicon in all
cases, not just in-process in iOS apps (the problem is not just about
coexistence of the two GLs, but actually about our ability to load
the accelerated renderer /at all/ in macCatalyst processes).

I left the runtime switching in place, because there is a future in
which we /can/ use CGL in non-iOS-app processes, but that future is
not now.

Bug: angleproject:5369
Change-Id: I9a523d038eeeeef81efa3b97771443db857e97c8
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2548316Reviewed-by: Jonah Ryan-Davis <jonahr@google.com>
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Commit-Queue: James Darpinian <jdarpinian@chromium.org>