[gnome-shell/wip/carlosg/fix-xwayland-shutdown] windowManager: Fix shutdown signal connection

[Carlos Garnacho <carlosg src gnome org>]

commit 6935cabd6f54a20f2abb54dd0ba26dcaa9467392
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sat Feb 29 23:42:29 2020 +0100

    windowManager: Fix shutdown signal connection
    
    This signal relied on mutter changes that were withdrawn
    and it was unintended to use here. Restore the usage of
    good old MetaDisplay::x11-display-closing.

 js/ui/windowManager.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)
---
diff --git a/js/ui/windowManager.js b/js/ui/windowManager.js
index d02d2e183b..9e15ba70a8 100644
--- a/js/ui/windowManager.js
+++ b/js/ui/windowManager.js
@@ -922,10 +922,9 @@ var WindowManager = class {
                 null);
             return true;
         });
-        global.display.connect('shutdown-xserver', (display, task) => {
+        global.display.connect('x11-display-closing', () => {
             Shell.util_stop_systemd_unit('gsd-xsettings.target', 'fail');
             IBusManager.getIBusManager().restartDaemon();
-            task.return_boolean(true);
         });
 
         Main.overview.connect('showing', () => {