[gnome-settings-daemon] xsettings: Fix segfault when unloading plugin

[Sebastien Bacher <sbacher src gnome org>]

commit 1d4dffeb704425d19f98332341d20f05ad11e62c
Author: Sebastien Bacher <seb128 ubuntu com>
Date:   Thu Oct 22 13:27:08 2015 +0200

    xsettings: Fix segfault when unloading plugin
    
    Disconnect the signal from plugin_settings when unloading the plugin
    so it's not called after the plugin has been freed.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=756958

 plugins/xsettings/gsd-xsettings-manager.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/plugins/xsettings/gsd-xsettings-manager.c b/plugins/xsettings/gsd-xsettings-manager.c
index 5ea7c2e..816485f 100644
--- a/plugins/xsettings/gsd-xsettings-manager.c
+++ b/plugins/xsettings/gsd-xsettings-manager.c
@@ -1334,6 +1334,7 @@ gnome_xsettings_manager_stop (GnomeXSettingsManager *manager)
         }
 
         if (p->plugin_settings != NULL) {
+                g_signal_handlers_disconnect_by_data (p->plugin_settings, manager);
                 g_object_unref (p->plugin_settings);
                 p->plugin_settings = NULL;
         }