[mutter] Revert "window-actor: Remove conditional checks for the shape region"

[Jasper St. Pierre <jstpierre src gnome org>]

commit e48c3dac878ec475ef99e89d9a54ae87d14ea057
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Wed Feb 6 00:02:02 2013 -0500

    Revert "window-actor: Remove conditional checks for the shape region"
    
    This reverts commit 84930f1d781e1432a3319ecea095d8da602498f8.

 src/compositor/meta-window-actor.c |   48 ++++++++++++++++++++++++++---------
 1 files changed, 35 insertions(+), 13 deletions(-)
---
diff --git a/src/compositor/meta-window-actor.c b/src/compositor/meta-window-actor.c
index 681321a..137a47b 100644
--- a/src/compositor/meta-window-actor.c
+++ b/src/compositor/meta-window-actor.c
@@ -68,7 +68,7 @@ struct _MetaWindowActorPrivate
 
   gchar *           desc;
 
-  /* A region that matches the shape of the window, including frame bounds */
+  /* If the window is shaped, a region that matches the shape */
   cairo_region_t   *shape_region;
   /* A rectangular region with the visible extents of the window */
   cairo_region_t   *bounding_region;
@@ -560,7 +560,16 @@ meta_window_actor_get_shape_bounds (MetaWindowActor       *self,
 {
   MetaWindowActorPrivate *priv = self->priv;
 
-  cairo_region_get_extents (priv->shape_region, bounds);
+  /* We need to be defensive here because there are corner cases
+   * where getting the shape fails on a window being destroyed
+   * and similar.
+   */
+  if (priv->shape_region)
+    cairo_region_get_extents (priv->shape_region, bounds);
+  else if (priv->bounding_region)
+    cairo_region_get_extents (priv->bounding_region, bounds);
+  else
+    bounds->x = bounds->y = bounds->width = bounds->height = 0;
 }
 
 static void
@@ -1604,7 +1613,12 @@ meta_window_actor_get_obscured_region (MetaWindowActor *self)
   MetaWindowActorPrivate *priv = self->priv;
 
   if (!priv->argb32 && priv->opacity == 0xff && priv->back_pixmap)
-    return priv->shape_region;
+    {
+      if (priv->shape_region)
+        return priv->shape_region;
+      else
+        return priv->bounding_region;
+    }
   else
     return NULL;
 }
@@ -1853,17 +1867,25 @@ check_needs_shadow (MetaWindowActor *self)
   if (*shadow_location == NULL && should_have_shadow)
     {
       if (priv->shadow_shape == NULL)
-        priv->shadow_shape = meta_window_shape_new (priv->shape_region);
-
-      MetaShadowFactory *factory = meta_shadow_factory_get_default ();
-      const char *shadow_class = meta_window_actor_get_shadow_class (self);
-      cairo_rectangle_int_t shape_bounds;
+        {
+          if (priv->shape_region)
+            priv->shadow_shape = meta_window_shape_new (priv->shape_region);
+          else if (priv->bounding_region)
+            priv->shadow_shape = meta_window_shape_new (priv->bounding_region);
+        }
 
-      meta_window_actor_get_shape_bounds (self, &shape_bounds);
-      *shadow_location = meta_shadow_factory_get_shadow (factory,
-                                                         priv->shadow_shape,
-                                                         shape_bounds.width, shape_bounds.height,
-                                                         shadow_class, appears_focused);
+      if (priv->shadow_shape != NULL)
+        {
+          MetaShadowFactory *factory = meta_shadow_factory_get_default ();
+          const char *shadow_class = meta_window_actor_get_shadow_class (self);
+          cairo_rectangle_int_t shape_bounds;
+
+          meta_window_actor_get_shape_bounds (self, &shape_bounds);
+          *shadow_location = meta_shadow_factory_get_shadow (factory,
+                                                             priv->shadow_shape,
+                                                             shape_bounds.width, shape_bounds.height,
+                                                             shadow_class, appears_focused);
+        }
     }
 
   if (old_shadow != NULL)