[mutter] clutter/paint-context: Add 'no-cursors' paint flag

[Jonas Ådahl <jadahl src gnome org>]

commit d2c3272eb7cb3e28f3d50e04a98f1fa799f5bac2
Author: Jonas Ådahl <jadahl gmail com>
Date:   Mon Apr 20 22:41:12 2020 +0200

    clutter/paint-context: Add 'no-cursors' paint flag
    
    Will be used by the stage to not paint the overlays. We skip all
    overlays since overlays are only ever used for pointer cursors when the
    hardware cursors cannot or should not be used.
    
    https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1207

 clutter/clutter/clutter-paint-context.h | 1 +
 src/backends/meta-stage.c               | 8 ++++++--
 2 files changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/clutter/clutter/clutter-paint-context.h b/clutter/clutter/clutter-paint-context.h
index 6b65fecac..f781728c3 100644
--- a/clutter/clutter/clutter-paint-context.h
+++ b/clutter/clutter/clutter-paint-context.h
@@ -32,6 +32,7 @@ typedef struct _ClutterPaintContext ClutterPaintContext;
 typedef enum _ClutterPaintFlag
 {
   CLUTTER_PAINT_FLAG_NONE = 0,
+  CLUTTER_PAINT_FLAG_NO_CURSORS = 1 << 0,
 } ClutterPaintFlag;
 
 #define CLUTTER_TYPE_PAINT_CONTEXT (clutter_paint_context_get_type ())
diff --git a/src/backends/meta-stage.c b/src/backends/meta-stage.c
index e5f156880..072241ec9 100644
--- a/src/backends/meta-stage.c
+++ b/src/backends/meta-stage.c
@@ -206,8 +206,12 @@ meta_stage_paint (ClutterActor        *actor,
 
   g_signal_emit (stage, signals[ACTORS_PAINTED], 0);
 
-  for (l = stage->overlays; l; l = l->next)
-    meta_overlay_paint (l->data, paint_context);
+  if (!(clutter_paint_context_get_paint_flags (paint_context) &
+        CLUTTER_PAINT_FLAG_NO_CURSORS))
+    {
+      for (l = stage->overlays; l; l = l->next)
+        meta_overlay_paint (l->data, paint_context);
+    }
 
   if (view)
     {