Obsolete gtk3 patch?

[Michael Forney <mforney%mforney.org@localhost>]

I noticed that x11/gtk3 has a patch (patch-gdk_quartz_gdkquartz-gtk-only.h)
which adds a file that already exists in the source tar.

It seems to me that the patch is obsolete and can be deleted, but
the contents of the file it adds is slightly different from the one
in the tar. I don't have access to a macOS machine to check whether
it still builds with the version in the tar.

Different patch(1) implementations handle this situation differently.
nbpatch inserts the version of the file from the patch before the
contents of the file from the tar, effectively replacing the version
in the tar with the one in the patch (due to include guards). GNU
patch errors out:

  => Applying pkgsrc patch /mnt/data/cvs/pkgsrc/x11/gtk3/patches/patch-gdk_quartz_gdkquartz-gtk-only.h
  The next patch would create the file gdk/quartz/gdkquartz-gtk-only.h,
  which already exists!  Assume -R? [n]
  Apply anyway? [n]
  Skipping patch.
  1 out of 1 hunk ignored
  Patch /mnt/data/cvs/pkgsrc/x11/gtk3/patches/patch-gdk_quartz_gdkquartz-gtk-only.h failed

I think we should fix this before 2021Q2 is released. Can someone
with a macOS machine check whether gtk3 still builds with the patch
deleted and the quartz option enabled?