[at-spi2-core] Fix a crash when parsing events

[Mike Gorse <mgorse src gnome org>]

commit 8a003957693f41d75e6291342a1b16434677f027
Author: Mike Gorse <mgorse suse com>
Date:   Tue Dec 4 23:54:55 2012 -0600

    Fix a crash when parsing events
    
    If an event listener specifies a detail for an event, but an event
    arrives with an empty detail, then libatspi might crash.

 atspi/atspi-event-listener.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/atspi/atspi-event-listener.c b/atspi/atspi-event-listener.c
index 9152054..bd8da50 100644
--- a/atspi/atspi-event-listener.c
+++ b/atspi/atspi-event-listener.c
@@ -802,6 +802,9 @@ detail_matches_listener (const char *event_detail, const char *listener_detail)
   if (!listener_detail)
     return TRUE;
 
+  if (!event_detail)
+    return (listener_detail ? FALSE : TRUE);
+
   return !(listener_detail [strcspn (listener_detail, ":")] == '\0'
                ? strncmp (listener_detail, event_detail,
                           strcspn (event_detail, ":"))