[gtk+] Don't ever invalidate the root window

[Alexander Larsson <alexl src gnome org>]

commit 7f92684237fe842621b2653cc8b46288646a61b3
Author: Alexander Larsson <alexl redhat com>
Date:   Mon Aug 10 14:08:37 2009 +0200

    Don't ever invalidate the root window
    
    This never worked before csw since the root window is never
    set as IS_MAPPED, but with the new viewable check (which is
    true for the root window) we could erronously queue exposes
    on the root window.
    
    This happened unexpectedly in bug 589369, where metacity
    got a GraphicsExpose event on the root window due to some
    graphics operation, queueing an expose which would be handled
    by clearing that area. That is fixed with this commit.

 gdk/gdkwindow.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/gdk/gdkwindow.c b/gdk/gdkwindow.c
index 7a000aa..fc0a237 100644
--- a/gdk/gdkwindow.c
+++ b/gdk/gdkwindow.c
@@ -5135,7 +5135,8 @@ gdk_window_invalidate_maybe_recurse (GdkWindow       *window,
 
   if (private->input_only ||
       !private->viewable ||
-      gdk_region_empty (region))
+      gdk_region_empty (region) ||
+      private->window_type == GDK_WINDOW_ROOT)
     return;
 
   visible_region = gdk_drawable_get_visible_region (window);