[mutter] restart: Request to hide the restart message if not accepted

[Marge Bot <marge-bot src gnome org>]

commit 42287a5f040f4d5eaa33646ab4d10f6de920d2cf
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Thu Jul 25 02:59:54 2019 +0200

    restart: Request to hide the restart message if not accepted
    
    In case the shell ignores or can't accept the restart request we should
    hide the message that has been just requested to be shown.
    
    As per ::show-restart-message signal documentation, this has to be done by
    emitting the signal with a NULL message.
    
    So follow the API properly in such case
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1780>

 src/core/restart.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)
---
diff --git a/src/core/restart.c b/src/core/restart.c
index 10a6bd0c9a..e9a5bfd27e 100644
--- a/src/core/restart.c
+++ b/src/core/restart.c
@@ -59,7 +59,12 @@ static void
 restart_check_ready (void)
 {
   if (restart_helper_started && restart_message_shown)
-    meta_display_request_restart (meta_get_display ());
+    {
+      MetaDisplay *display = meta_get_display ();
+
+      if (!meta_display_request_restart (display))
+        meta_display_show_restart_message (display, NULL);
+    }
 }
 
 static void