[gtk+] Mention gdk_window_restack

[Matthias Clasen <matthiasc src gnome org>]

commit d497e8ed74991f3c7fe320d964db14514f6be233
Author: Matthias Clasen <mclasen redhat com>
Date:   Thu Sep 10 13:52:29 2009 -0400

    Mention gdk_window_restack
    
    It is probably worth mentioning this function by name, since we've
    added it explicitly to easy porting...

 .../reference/gtk/migrating-ClientSideWindows.sgml |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/docs/reference/gtk/migrating-ClientSideWindows.sgml b/docs/reference/gtk/migrating-ClientSideWindows.sgml
index 3860ee5..b1721b2 100644
--- a/docs/reference/gtk/migrating-ClientSideWindows.sgml
+++ b/docs/reference/gtk/migrating-ClientSideWindows.sgml
@@ -30,6 +30,8 @@
     example that we've seen is changing the child window stacking order
     using XRestackWindows(). Fixing this properly requires to fix the code
     to use GDK functions to achieve whatever it is trying to achieve.
+    To make this easier in the case of stacking order changes, we've added
+    a gdk_window_restack() function.
   </para>
 
   <para>