[mutter] clutter/stage-view: Add API to check if a shadowfb is used

[Marge Bot <marge-bot src gnome org>]

commit b071a8366d70b3a24f1230e594453e664f5d590a
Author: Robert Mader <robert mader posteo de>
Date:   Thu Sep 1 21:03:12 2022 +0200

    clutter/stage-view: Add API to check if a shadowfb is used
    
    As a more readable alternative to checking GObject properties.
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2468>

 clutter/clutter/clutter-stage-view.c | 9 +++++++++
 clutter/clutter/clutter-stage-view.h | 3 +++
 2 files changed, 12 insertions(+)
---
diff --git a/clutter/clutter/clutter-stage-view.c b/clutter/clutter/clutter-stage-view.c
index 22c7647996..aa98e6a629 100644
--- a/clutter/clutter/clutter-stage-view.c
+++ b/clutter/clutter/clutter-stage-view.c
@@ -1120,6 +1120,15 @@ clutter_stage_view_get_frame_clock (ClutterStageView *view)
   return priv->frame_clock;
 }
 
+gboolean
+clutter_stage_view_has_shadowfb (ClutterStageView *view)
+{
+  ClutterStageViewPrivate *priv =
+    clutter_stage_view_get_instance_private (view);
+
+  return priv->use_shadowfb;
+}
+
 static void
 handle_frame_clock_before_frame (ClutterFrameClock *frame_clock,
                                  int64_t            frame_count,
diff --git a/clutter/clutter/clutter-stage-view.h b/clutter/clutter/clutter-stage-view.h
index c2cf76abf6..c8974d00d3 100644
--- a/clutter/clutter/clutter-stage-view.h
+++ b/clutter/clutter/clutter-stage-view.h
@@ -82,4 +82,7 @@ CoglScanout * clutter_stage_view_peek_scanout (ClutterStageView *view);
 CLUTTER_EXPORT
 float clutter_stage_view_get_refresh_rate (ClutterStageView *view);
 
+CLUTTER_EXPORT
+gboolean clutter_stage_view_has_shadowfb (ClutterStageView *view);
+
 #endif /* __CLUTTER_STAGE_VIEW_H__ */