[gnome-shell] Avoid warnings on leave-event for widgets tracking hover

[Giovanni Campagna <gcampagna src gnome org>]

commit a915af4b30a5692fd72db861a5c5280059c72327
Author: Giovanni Campagna <gcampagna src gnome org>
Date:   Sun Oct 24 14:30:03 2010 +0200

    Avoid warnings on leave-event for widgets tracking hover
    
    ClutterCrossingEvent->related can be NULL if the pointer is not under
    any actor. Unconditionally set hover to FALSE in that case.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=633028

 src/st/st-widget.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/st/st-widget.c b/src/st/st-widget.c
index e5f3050..48c7a3d 100644
--- a/src/st/st-widget.c
+++ b/src/st/st-widget.c
@@ -594,7 +594,7 @@ st_widget_leave (ClutterActor         *actor,
 
   if (priv->track_hover)
     {
-      if (!clutter_actor_contains (actor, event->related))
+      if (!event->related || !clutter_actor_contains (actor, event->related))
         st_widget_set_hover (ST_WIDGET (actor), FALSE);
     }