[mutter] monitor-manager: Use better error code when using the wrong API

[Jonas Ådahl <jadahl src gnome org>]

commit 9a5b94a34079b24a03918017896e76713475a647
Author: Jonas Ådahl <jadahl gmail com>
Date:   Tue Feb 14 18:33:03 2017 +0800

    monitor-manager: Use better error code when using the wrong API
    
    It has nothing to do with permissions, so 'not-supported' is a bit
    better.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=777732

 src/backends/meta-monitor-manager.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/backends/meta-monitor-manager.c b/src/backends/meta-monitor-manager.c
index 6ba95f2..e60f93a 100644
--- a/src/backends/meta-monitor-manager.c
+++ b/src/backends/meta-monitor-manager.c
@@ -972,7 +972,7 @@ meta_monitor_manager_legacy_handle_apply_configuration  (MetaDBusDisplayConfig *
   if (manager->config_manager)
     {
       g_dbus_method_invocation_return_error (invocation, G_DBUS_ERROR,
-                                             G_DBUS_ERROR_ACCESS_DENIED,
+                                             G_DBUS_ERROR_NOT_SUPPORTED,
                                              "Used old configuration API with new configuration system");
       return TRUE;
     }