[vino] Check if mDNS is active before asking for a local hostname.

[Jonh Wendell <jwendell src gnome org>]

commit 58af35a045b0ee6b4f13c76246a5eb38738e358f
Author: Jonh Wendell <jwendell gnome org>
Date:   Mon Oct 19 15:28:53 2009 -0300

    Check if mDNS is active before asking for a local hostname.
    
    Closes Ubuntu #440712.

 server/vino-mdns.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/server/vino-mdns.c b/server/vino-mdns.c
index 0a742f4..4f7e693 100644
--- a/server/vino-mdns.c
+++ b/server/vino-mdns.c
@@ -356,7 +356,7 @@ vino_mdns_shutdown (void)
 const char *
 vino_mdns_get_hostname (void)
 {
-  return avahi_client_get_host_name_fqdn (mdns_client);
+  return mdns_client ? avahi_client_get_host_name_fqdn (mdns_client) : "";
 }
 
 #else /* !defined (VINO_HAVE_AVAHI) */