[gthumb] show the app menu on the headerbar if the shell doesn't show it

[Paolo Bacchilega <paobac src gnome org>]

commit 67ccaa344ad46536e0bbffa03acdf305d83ac904
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Sun Mar 29 16:49:59 2015 +0200

    show the app menu on the headerbar if the shell doesn't show it

 gthumb/gth-window.c |   25 +++++++++++++++++++++++++
 gthumb/main.c       |    6 ------
 2 files changed, 25 insertions(+), 6 deletions(-)
---
diff --git a/gthumb/gth-window.c b/gthumb/gth-window.c
index b4ade2f..ac059c9 100644
--- a/gthumb/gth-window.c
+++ b/gthumb/gth-window.c
@@ -115,6 +115,31 @@ _gth_window_add_header_bar (GthWindow *self)
        self->priv->headerbar = gtk_header_bar_new ();
        gtk_widget_show (self->priv->headerbar);
        gtk_header_bar_set_show_close_button (GTK_HEADER_BAR (self->priv->headerbar), TRUE);
+
+       {
+               gboolean  shell_shows_app_menu;
+               char     *decoration_layout;
+
+               g_object_get (gtk_settings_get_default (),
+                             "gtk-shell-shows-app-menu", &shell_shows_app_menu,
+                             "gtk-decoration-layout", &decoration_layout,
+                             NULL);
+               if (! shell_shows_app_menu && ((decoration_layout == NULL) || (strstr (decoration_layout, 
"menu") == NULL))) {
+                       gboolean  left_part_is_empty;
+                       char     *new_layout;
+
+                       /* add 'menu' to the left */
+
+                       left_part_is_empty = (decoration_layout == NULL) || (decoration_layout[0] == '\0') || 
(decoration_layout[0] == ':');
+                       new_layout = g_strconcat ("menu", (left_part_is_empty ? "" : ","), decoration_layout, 
NULL);
+                       gtk_header_bar_set_decoration_layout (GTK_HEADER_BAR (self->priv->headerbar), 
new_layout);
+
+                       g_free (new_layout);
+               }
+
+               g_free (decoration_layout);
+       }
+
        self->priv->title = gth_window_title_new ();
        gtk_widget_show (self->priv->title);
        gtk_header_bar_set_custom_title (GTK_HEADER_BAR (self->priv->headerbar), self->priv->title);
diff --git a/gthumb/main.c b/gthumb/main.c
index 38e49e3..21098f5 100644
--- a/gthumb/main.c
+++ b/gthumb/main.c
@@ -221,12 +221,6 @@ _gth_application_initialize_app_menu (GApplication *application)
        gboolean    show_app_menu;
        GtkBuilder *builder;
 
-       g_object_get (gtk_settings_get_default (),
-                     "gtk-shell-shows-app-menu", &show_app_menu,
-                     NULL);
-       if (! show_app_menu)
-               return;
-
        g_action_map_add_action_entries (G_ACTION_MAP (application),
                                         app_menu_entries,
                                         G_N_ELEMENTS (app_menu_entries),