[gnome-shell] introspect: Remove unused variable

[Jonas Ådahl <jadahl src gnome org>]

commit a1c39006309c680aaa7417917af4d2b7ae3e754a
Author: Florian Müllner <fmuellner gnome org>
Date:   Thu May 16 09:48:59 2019 +0000

    introspect: Remove unused variable
    
    https://gitlab.gnome.org/GNOME/gnome-shell/issues/1289

 js/misc/introspect.js | 2 --
 1 file changed, 2 deletions(-)
---
diff --git a/js/misc/introspect.js b/js/misc/introspect.js
index f7a7f2fe6..3ff48b016 100644
--- a/js/misc/introspect.js
+++ b/js/misc/introspect.js
@@ -42,8 +42,6 @@ var IntrospectService = class {
     }
 
     _isStandaloneApp(app) {
-        let windows = app.get_windows();
-
         return app.get_windows().some(w => w.transient_for == null);
     }