[gnome-ostree] manifest: Explicitly enable X11 backend

[Jasper St. Pierre <jstpierre src gnome org>]

commit 3147781564b53d53726011a1fca844f496f9abe8
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Sun Aug 11 20:11:19 2013 -0400

    manifest: Explicitly enable X11 backend
    
    GDK complains it has no backends without this.

 manifest.json |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/manifest.json b/manifest.json
index bb26f0d..d11c0cd 100644
--- a/manifest.json
+++ b/manifest.json
@@ -501,7 +501,7 @@
                 "branch": "gtk-engines-2-22"},
 
                {"src": "gnome:gtk+",
-                "config-opts": ["--enable-installed-tests", "--disable-wayland-backend"],
+                "config-opts": ["--enable-installed-tests", "--disable-wayland-backend", 
"--enable-x11-backend"],
                 "name": "gtk3"},
 
                {"src": "fd:plymouth",