[libchamplain] Provide our own gtk_widget_get_window() if GTK is missing it.

[Pierre-Luc Beaudoin <plbeaudoin src gnome org>]

commit 32efe7e3b386731ae8ae7e7a2a170a33d7ea993b
Author: Emmanuel Rodriguez <emmanuel rodriguez gmail com>
Date:   Sun Aug 2 23:30:40 2009 +0200

    Provide our own gtk_widget_get_window() if GTK is missing it.
    
    Debian lenny has an older version of GTK (2.12) that's missing gtk_widget_get_window().

 champlain-gtk/gtk-champlain-embed.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/champlain-gtk/gtk-champlain-embed.c b/champlain-gtk/gtk-champlain-embed.c
index 5330191..a3d4839 100644
--- a/champlain-gtk/gtk-champlain-embed.c
+++ b/champlain-gtk/gtk-champlain-embed.c
@@ -35,6 +35,10 @@
 
 #include "gtk-champlain-embed.h"
 
+#if (GTK_MAJOR_VERSION == 2 && GTK_MINOR_VERSION <= 12)
+#define gtk_widget_get_window(widget) ((widget)->window)
+#endif
+
 enum
 {
   /* normal signals */