[gtk+/gtk-2-18] Add supports_native_bg to GdkWindowImpl

[Alexander Larsson <alexl src gnome org>]

commit 92efb23b4b416c15c709b5ea75444bb844f9f58a
Author: Alexander Larsson <alexl redhat com>
Date:   Tue Nov 3 15:38:35 2009 +0100

    Add supports_native_bg to GdkWindowImpl
    
    Backends that support native window background setting (and that clears
    new window areas to this color/pixmap) should set this to true.
    
    Currently only X11 supports this.
    (cherry picked from commit 39993f147f05a3711b415635c592200f28db5dcd)

 gdk/gdkwindowimpl.h     |    1 +
 gdk/x11/gdkwindow-x11.c |    1 +
 2 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/gdk/gdkwindowimpl.h b/gdk/gdkwindowimpl.h
index 00f2f1b..3a5029b 100644
--- a/gdk/gdkwindowimpl.h
+++ b/gdk/gdkwindowimpl.h
@@ -146,6 +146,7 @@ struct _GdkWindowImplIface
   void         (* input_window_destroy) (GdkWindow       *window);
   void         (* input_window_crossing)(GdkWindow       *window,
 					 gboolean         enter);
+  gboolean     supports_native_bg;
 };
 
 /* Interface Functions */
diff --git a/gdk/x11/gdkwindow-x11.c b/gdk/x11/gdkwindow-x11.c
index a8dd83b..c215e87 100644
--- a/gdk/x11/gdkwindow-x11.c
+++ b/gdk/x11/gdkwindow-x11.c
@@ -5606,6 +5606,7 @@ gdk_window_impl_iface_init (GdkWindowImplIface *iface)
   iface->destroy = _gdk_x11_window_destroy;
   iface->input_window_destroy = _gdk_input_window_destroy;
   iface->input_window_crossing = _gdk_input_crossing_event;
+  iface->supports_native_bg = TRUE;
 }
 
 #define __GDK_WINDOW_X11_C__