[empathy] don't update Alias.Nickname if not needed

[Guillaume Desmottes <gdesmott src gnome org>]

commit 1e2ef0f3c681511d1b1e82a51f82b52b9414605f
Author: Guillaume Desmottes <guillaume desmottes collabora co uk>
Date:   Thu Mar 10 12:04:37 2011 +0100

    don't update Alias.Nickname if not needed

 libempathy-gtk/empathy-contact-widget.c |   11 +++++++++--
 1 files changed, 9 insertions(+), 2 deletions(-)
---
diff --git a/libempathy-gtk/empathy-contact-widget.c b/libempathy-gtk/empathy-contact-widget.c
index b82ad16..b956e22 100644
--- a/libempathy-gtk/empathy-contact-widget.c
+++ b/libempathy-gtk/empathy-contact-widget.c
@@ -1228,11 +1228,18 @@ contact_widget_entry_alias_focus_event_cb (GtkEditable *editable,
       if (empathy_contact_is_user (information->contact))
         {
           TpAccount * account;
+          const gchar *current_nickname;
 
           account = empathy_contact_get_account (information->contact);
+          current_nickname = tp_account_get_nickname (account);
 
-          DEBUG ("Set Account.Nickname to %s", alias);
-          tp_account_set_nickname_async (account, alias, set_nickname_cb, NULL);
+          if (tp_strdiff (current_nickname, alias))
+            {
+              DEBUG ("Set Account.Nickname to %s", alias);
+
+              tp_account_set_nickname_async (account, alias, set_nickname_cb,
+                  NULL);
+            }
         }
       else
         {