[metacity] libmetacity: don't expose button layout functions

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 6a1e3c1b658e997049ae0ea36b05c7cc30033c28
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Thu Aug 18 18:59:35 2016 +0300

    libmetacity: don't expose button layout functions

 libmetacity/meta-button-layout-private.h |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/libmetacity/meta-button-layout-private.h b/libmetacity/meta-button-layout-private.h
index d4397ef..00738d9 100644
--- a/libmetacity/meta-button-layout-private.h
+++ b/libmetacity/meta-button-layout-private.h
@@ -32,9 +32,11 @@ typedef struct
   gint        n_right_buttons;
 } MetaButtonLayout;
 
+G_GNUC_INTERNAL
 MetaButtonLayout *meta_button_layout_new  (const gchar      *str,
                                            gboolean          invert);
 
+G_GNUC_INTERNAL
 void              meta_button_layout_free (MetaButtonLayout *layout);
 
 G_END_DECLS