[mutter] surface-actor: Fix memory leak

[Jonas Ådahl <jadahl src gnome org>]

commit 1d2004524728d337b0e98bedfc360549b9ee7d0e
Author: Robert Mader <robert mader posteo de>
Date:   Tue Mar 17 20:57:18 2020 +0100

    surface-actor: Fix memory leak
    
    When we create a new region for an opaque texture we need to free it.
    While on it, simplify the check slightly.
    
    https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1108

 src/compositor/meta-surface-actor.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)
---
diff --git a/src/compositor/meta-surface-actor.c b/src/compositor/meta-surface-actor.c
index ff66f3c0a..41aa5a26d 100644
--- a/src/compositor/meta-surface-actor.c
+++ b/src/compositor/meta-surface-actor.c
@@ -285,8 +285,11 @@ meta_surface_actor_cull_out (MetaCullable   *cullable,
       int geometry_scale = 1;
 
       opaque_region = meta_shaped_texture_get_opaque_region (priv->texture);
-
-      if (!opaque_region && meta_shaped_texture_is_opaque (priv->texture))
+      if (opaque_region)
+        {
+          cairo_region_reference (opaque_region);
+        }
+      else if (meta_shaped_texture_is_opaque (priv->texture))
         {
           cairo_rectangle_int_t rect;
 
@@ -297,9 +300,10 @@ meta_surface_actor_cull_out (MetaCullable   *cullable,
 
           opaque_region = cairo_region_create_rectangle (&rect);
         }
-
-      if (!opaque_region)
-        return;
+      else
+        {
+          return;
+        }
 
       window_actor =
         meta_window_actor_from_actor (CLUTTER_ACTOR (surface_actor));
@@ -313,6 +317,7 @@ meta_surface_actor_cull_out (MetaCullable   *cullable,
       if (clip_region)
         cairo_region_subtract (clip_region, scaled_opaque_region);
 
+      cairo_region_destroy (opaque_region);
       cairo_region_destroy (scaled_opaque_region);
     }
 }