[gtk+/treeview-refactor] Only show Desktop in file chooser button if there is one

[Tristan Van Berkom <tvb src gnome org>]

commit 7ca240916f0000c44812d41468b9e1f9fb343636
Author: Christian Dywan <christian twotoasts de>
Date:   Fri Oct 22 16:07:25 2010 +0200

    Only show Desktop in file chooser button if there is one
    
    Fixes: https://bugzilla.gnome.org/show_bug.cgi?id=632894

 gtk/gtkfilechooserbutton.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkfilechooserbutton.c b/gtk/gtkfilechooserbutton.c
index 471be29..d0b0268 100644
--- a/gtk/gtkfilechooserbutton.c
+++ b/gtk/gtkfilechooserbutton.c
@@ -1685,7 +1685,10 @@ model_add_special (GtkFileChooserButton *button)
 
   desktopdir = g_get_user_special_dir (G_USER_DIRECTORY_DESKTOP);
 
-  if (desktopdir)
+  /* "To disable a directory, point it to the homedir."
+   * See http://freedesktop.org/wiki/Software/xdg-user-dirs
+   **/
+  if (g_strcmp0 (desktopdir, g_get_home_dir ()) != 0)
     {
       GtkTreePath *tree_path;
       GCancellable *cancellable;