[glib] Don't try to ref NULL pointer in g_desktop_app_info_dup()

[Paul Pogonyshev <paulp src gnome org>]

commit 2fff3026efbaf7e480d1a166c7166c44c6643567
Author: Paul Pogonyshev <pogonyshev gmx net>
Date:   Mon May 4 22:32:35 2009 +0300

    Don't try to ref NULL pointer in g_desktop_app_info_dup()
    
    Fixes bug #573246.
---
 gio/gdesktopappinfo.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/gio/gdesktopappinfo.c b/gio/gdesktopappinfo.c
index fcd7737..fea0761 100644
--- a/gio/gdesktopappinfo.c
+++ b/gio/gdesktopappinfo.c
@@ -417,7 +417,8 @@ g_desktop_app_info_dup (GAppInfo *appinfo)
   new_info->comment = g_strdup (info->comment);
   new_info->nodisplay = info->nodisplay;
   new_info->icon_name = g_strdup (info->icon_name);
-  new_info->icon = g_object_ref (info->icon);
+  if (info->icon)
+    new_info->icon = g_object_ref (info->icon);
   new_info->only_show_in = g_strdupv (info->only_show_in);
   new_info->not_show_in = g_strdupv (info->not_show_in);
   new_info->try_exec = g_strdup (info->try_exec);