[metacity] prefs: don't reload theme if not needed

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 545a1c736319c450a86c75bd27b7ac83918c0fb3
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Thu Jun 9 19:24:41 2016 +0300

    prefs: don't reload theme if not needed
    
    When using Metacity theme we don't need to realod it when
    gtk-theme-name changes. It is needed only with GTK+ theme.

 src/core/prefs.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/src/core/prefs.c b/src/core/prefs.c
index 4044982..8a06291 100644
--- a/src/core/prefs.c
+++ b/src/core/prefs.c
@@ -870,7 +870,8 @@ gtk_theme_name_changed (GtkSettings *settings,
                         GParamSpec  *pspec,
                         gpointer     user_data)
 {
-  queue_changed (META_PREF_THEME_NAME);
+  if (current_theme_type == META_THEME_TYPE_GTK)
+    queue_changed (META_PREF_THEME_NAME);
 }
 
 static void