[gtk+/gtk-3-22] scalebutton: Fix comparison for empty icon list

[Daniel Boles <dboles src gnome org>]

commit 8db97768758dc4dc1f30abc849d6a0e9f74d3aaf
Author: Timm Bäder <mail baedert org>
Date:   Sun Oct 8 20:15:39 2017 +0200

    scalebutton: Fix comparison for empty icon list
    
    https://bugzilla.gnome.org/show_bug.cgi?id=786220

 gtk/gtkscalebutton.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkscalebutton.c b/gtk/gtkscalebutton.c
index 8423cd6..2b331b0 100644
--- a/gtk/gtkscalebutton.c
+++ b/gtk/gtkscalebutton.c
@@ -985,7 +985,7 @@ gtk_scale_button_update_icon (GtkScaleButton *button)
   const gchar *name;
   guint num_icons;
 
-  if (!priv->icon_list || ((char*)priv->icon_list)[0] == '\0')
+  if (!priv->icon_list || priv->icon_list[0][0] == '\0')
     {
       gtk_image_set_from_icon_name (GTK_IMAGE (priv->image),
                                     "image-missing",