[gtk] Mark the window-show-contents-on-map.ui reftest as xfail

[Matthias Clasen <matthiasc src gnome org>]

commit 2caf283323463045e252495a702b56deb0cf5a4e
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Dec 8 12:04:47 2020 -0500

    Mark the window-show-contents-on-map.ui reftest as xfail
    
    We know now what the test is trying to test, just lack
    the right plumbing to do it properly. So, keep the test
    around, marked as expected fail.

 testsuite/reftests/meson.build | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/testsuite/reftests/meson.build b/testsuite/reftests/meson.build
index 8df36fab93..a7b4eb0d27 100644
--- a/testsuite/reftests/meson.build
+++ b/testsuite/reftests/meson.build
@@ -448,6 +448,8 @@ xfails = [
   'sizegroups-evolution-identity-page.ui',
   # these depend on details of text layout
   'label-sizing.ui',
+  # needs a better way to perform delayed actions
+  'window-show-contents-on-map.ui',
 ]
 
 reftest_env = environment()