[gtk+] x11: Relax requirements for setting ParentRelative

[Matthias Clasen <matthiasc src gnome org>]

commit 374bedc0e2c208ee3fe0bfc698841e5c093e2905
Author: Evangelos Foutras <evangelos foutrelis com>
Date:   Sat Apr 11 11:20:56 2015 +0300

    x11: Relax requirements for setting ParentRelative
    
    XSetWindowBackgroundPixmap() will throw BadMatch only in the case of a
    different parent window depth. Different visuals are fine and actually
    expected in Gtk+ 3.16 (since we don't stick to the system default visual
    but try to pick a better one).
    
    https://bugzilla.gnome.org/show_bug.cgi?id=747524

 gdk/x11/gdkwindow-x11.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/gdk/x11/gdkwindow-x11.c b/gdk/x11/gdkwindow-x11.c
index 25b5e2b..1ace677 100644
--- a/gdk/x11/gdkwindow-x11.c
+++ b/gdk/x11/gdkwindow-x11.c
@@ -2963,15 +2963,15 @@ gdk_window_x11_set_background (GdkWindow      *window,
     {
       GdkWindow *parent;
 
-      /* X throws BadMatch if the parent has a different visual when
+      /* X throws BadMatch if the parent has a different depth when
        * using ParentRelative */
       parent = gdk_window_get_parent (window);
-      if (parent && gdk_window_get_visual (parent) == gdk_window_get_visual (window))
+      if (parent && window->depth != parent->depth)
         XSetWindowBackgroundPixmap (GDK_WINDOW_XDISPLAY (window),
-                                    GDK_WINDOW_XID (window), ParentRelative);
+                                    GDK_WINDOW_XID (window), None);
       else
         XSetWindowBackgroundPixmap (GDK_WINDOW_XDISPLAY (window),
-                                    GDK_WINDOW_XID (window), None);
+                                    GDK_WINDOW_XID (window), ParentRelative);
       return;
     }