[gtk+] window: Fix gtk_window_set_geometry_hints documentation

[Debarshi Ray <debarshir src gnome org>]

commit 27a1b50bc63553909abf3958837114b65313a445
Author: Debarshi Ray <debarshir gnome org>
Date:   Tue Mar 29 19:29:31 2016 +0200

    window: Fix gtk_window_set_geometry_hints documentation
    
    The geometry_widget parameter is ignored from 3.20 onwards [1], not
    3.18 as mentioned in the documentation.
    
    [1] commit 08974a1e9a6099a5a94b9d56970dbf96e473ba87
    
    https://bugzilla.gnome.org/show_bug.cgi?id=764321

 gtk/gtkwindow.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index 83ad216..395b781 100644
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -3996,7 +3996,7 @@ gtk_window_get_geometry_info (GtkWindow *window,
  * gtk_window_set_geometry_hints:
  * @window: a #GtkWindow
  * @geometry_widget: (allow-none): widget the geometry hints used to be applied to
- *   or %NULL. Since 3.18 this argument is ignored and GTK behaves as if %NULL was
+ *   or %NULL. Since 3.20 this argument is ignored and GTK behaves as if %NULL was
  *   set.
  * @geometry: (allow-none): struct containing geometry information or %NULL
  * @geom_mask: mask indicating which struct fields should be paid attention to