[gnome-shell] shellDBus: Actually make ScreenTransitionAsync async

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

commit 8ba7f0f4a902439f87c7c9c887b385f9fa85384f
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Mon Mar 28 15:25:41 2022 +0200

    shellDBus: Actually make ScreenTransitionAsync async
    
    We called such function async but we didn't awaited for the
    checkInvocation result in the proper way.
    
    So on failure the shell would report an unhandled promise rejection.
    
    Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2258>

 js/ui/shellDBus.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/js/ui/shellDBus.js b/js/ui/shellDBus.js
index 8faa112eaf..edc16eb872 100644
--- a/js/ui/shellDBus.js
+++ b/js/ui/shellDBus.js
@@ -253,9 +253,9 @@ var GnomeShell = class {
         invocation.return_value(GLib.Variant.new('(b)', [ungrabSucceeded]));
     }
 
-    ScreenTransitionAsync(params, invocation) {
+    async ScreenTransitionAsync(params, invocation) {
         try {
-            this._senderChecker.checkInvocation(invocation);
+            await this._senderChecker.checkInvocation(invocation);
         } catch (e) {
             invocation.return_gerror(e);
             return;