[empathy] Fix a critical warning

[Michael Catanzaro <mcatanzaro src gnome org>]

commit c93fa8cdd89e95486129bdaea693b7e98694e70a
Author: Michael Catanzaro <mcatanzaro igalia com>
Date:   Sat Jan 16 06:38:30 2016 -0600

    Fix a critical warning
    
    GLib-CRITICAL **: Source ID 8795 was not found when attempting to
    remove it

 libempathy-gtk/empathy-chat.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/libempathy-gtk/empathy-chat.c b/libempathy-gtk/empathy-chat.c
index fc35bec..028f5ab 100644
--- a/libempathy-gtk/empathy-chat.c
+++ b/libempathy-gtk/empathy-chat.c
@@ -3196,6 +3196,8 @@ save_paned_pos_timeout (gpointer data)
        EmpathyChat *self = data;
        gint hpaned_pos;
 
+       self->priv->save_paned_pos_id = 0;
+
        hpaned_pos = gtk_paned_get_position (GTK_PANED (self->priv->hpaned));
 
        g_settings_set_int (self->priv->gsettings_ui,