[mutter/wip/carlosg/clip-regions: 4/6] clutter/cogl: Ensure we set dirty pixel if there's no region

[Carlos Garnacho <carlosg src gnome org>]

commit 23d7c0e1e5cbe712442df2f9e4c27b7d8ccb294f
Author: Carlos Garnacho <carlosg gnome org>
Date:   Tue Jul 30 23:46:51 2019 +0200

    clutter/cogl: Ensure we set dirty pixel if there's no region
    
    This may happen on startup, causing a crash.

 clutter/clutter/cogl/clutter-stage-cogl.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)
---
diff --git a/clutter/clutter/cogl/clutter-stage-cogl.c b/clutter/clutter/cogl/clutter-stage-cogl.c
index 9ad1bf8f3..3f9b4dd8d 100644
--- a/clutter/clutter/cogl/clutter-stage-cogl.c
+++ b/clutter/clutter/cogl/clutter-stage-cogl.c
@@ -1142,9 +1142,17 @@ clutter_stage_cogl_get_dirty_pixel (ClutterStageWindow *stage_window,
       clutter_stage_view_get_layout (view, &view_layout);
 
       fb_damage = view_priv->damage_history[DAMAGE_HISTORY (view_priv->damage_index - 1)];
-      cairo_region_get_extents (fb_damage, &fb_damage_rect);
-      *x = fb_damage_rect.x / fb_scale;
-      *y = fb_damage_rect.y / fb_scale;
+      if (fb_damage)
+        {
+          cairo_region_get_extents (fb_damage, &fb_damage_rect);
+          *x = fb_damage_rect.x / fb_scale;
+          *y = fb_damage_rect.y / fb_scale;
+        }
+      else
+        {
+          *x = 0;
+          *y = 0;
+        }
     }
 }