[glib] win32: fix build after bug 674452

[Matthias Clasen <matthiasc src gnome org>]

commit af3b1674cd65e1d650fb82bc93483391b99feb50
Author: Marc-Andrà Lureau <marcandre lureau gmail com>
Date:   Tue Jul 3 20:04:05 2012 +0200

    win32: fix build after bug 674452

 gio/gcontenttype.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gio/gcontenttype.c b/gio/gcontenttype.c
index dc48411..b91835e 100644
--- a/gio/gcontenttype.c
+++ b/gio/gcontenttype.c
@@ -332,7 +332,7 @@ g_content_type_guess (const gchar  *filename,
 
   /* our test suite and potentially other code used -1 in the past, which is
    * not documented and not allowed; guard against that */
-  g_return_val_if_fail (data_size != (gsize) -1, g_strdup (XDG_MIME_TYPE_UNKNOWN));
+  g_return_val_if_fail (data_size != (gsize) -1, g_strdup ("*"));
 
   if (filename)
     {