[gtk+] gdk: Document gdk_window_add_filter()+XGenericEvents behavior

[Carlos Garnacho <carlosg src gnome org>]

commit 1b53741e4c15e3923e614cdb707174033f0013e0
Author: Carlos Garnacho <carlosg gnome org>
Date:   Wed May 18 21:50:26 2011 +0200

    gdk: Document gdk_window_add_filter()+XGenericEvents behavior

 gdk/gdkwindow.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/gdk/gdkwindow.c b/gdk/gdkwindow.c
index 840fdbf..0be4656 100644
--- a/gdk/gdkwindow.c
+++ b/gdk/gdkwindow.c
@@ -2410,6 +2410,10 @@ gdk_window_peek_children (GdkWindow *window)
  *
  * See gdk_display_add_client_message_filter() if you are interested
  * in X ClientMessage events.
+ *
+ * If you are interested in X GenericEvents, bear in mind that
+ * XGetEventData() has been already called on the event, and
+ * XFreeEventData() must not be called within @function.
  **/
 void
 gdk_window_add_filter (GdkWindow     *window,