shell-util: Remove shell_util_icon_from_string

GJS doesn't need to be able to represent interfaces for you to be able to
access an interface method, so Gio.icon_new_for_string works fine.

https://bugzilla.gnome.org/show_bug.cgi?id=661231

src/shell-util.c

@@ -395,22 +395,6 @@ shell_util_get_icon_for_uri (const char *text_uri)
   return g_themed_icon_new ("gtk-file");
 }
 
-/**
- * shell_util_icon_from_string:
- * @string: a stringified #GIcon
- *
- * A static method equivalent to g_icon_new_for_string, workaround
- * for GJS not being able to represent Gio.Icon (which is an interface,
- * not a class).
- *
- * Returns: (transfer full): the icon which is represented by @string
- */
-GIcon *
-shell_util_icon_from_string (const char *string, GError **error)
-{
-  return g_icon_new_for_string (string, error);
-}
-
 static void
 stop_pick (ClutterActor       *actor,
            const ClutterColor *color)

src/shell-util.h

@@ -11,8 +11,6 @@ G_BEGIN_DECLS
 
 char    *shell_util_get_label_for_uri          (const char       *text_uri);
 GIcon   *shell_util_get_icon_for_uri           (const char       *text_uri);
-GIcon   *shell_util_icon_from_string           (const char       *string,
-                                                GError          **error);
 
 void     shell_util_set_hidden_from_pick       (ClutterActor     *actor,
                                                 gboolean          hidden);