[gtk/wip/chergert/quartz4u] use CGContext

[Christian Hergert <chergert src gnome org>]

commit fe3fee962e319955657bf44ca561cb12aa2ec1f6
Author: Christian Hergert <chergert redhat com>
Date:   Fri May 1 15:34:03 2020 -0700

    use CGContext

 gdk/macos/gdkmacoscairocontext.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/gdk/macos/gdkmacoscairocontext.c b/gdk/macos/gdkmacoscairocontext.c
index b9f4055ea9..db5dfda164 100644
--- a/gdk/macos/gdkmacoscairocontext.c
+++ b/gdk/macos/gdkmacoscairocontext.c
@@ -54,7 +54,7 @@ create_cairo_surface_for_surface (GdkSurface *surface)
 
   g_assert (GDK_IS_MACOS_SURFACE (surface));
 
-  cg = NSGraphicsContext.currentContext.graphicsPort;
+  cg = NSGraphicsContext.currentContext.CGContext;
   display = gdk_surface_get_display (surface);
   scale = gdk_surface_get_scale_factor (surface);
   width = scale * gdk_surface_get_width (surface);