[gnome-shell] CyclerPopup: Check for type using constructor

[Florian Müllner <fmuellner src gnome org>]

commit 3a3f9aa008e709e0a3c3535434efffb0231e4279
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Thu Apr 18 15:50:21 2019 -0500

    CyclerPopup: Check for type using constructor
    
    Classes that are sub-classes of GObject don't use a constructor per se, so we
    can't check for new.target (as this is undefined) in _init.
    
    Then compare the current constructor name instead.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/503

 js/ui/altTab.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/js/ui/altTab.js b/js/ui/altTab.js
index fb9c875c8..0212992be 100644
--- a/js/ui/altTab.js
+++ b/js/ui/altTab.js
@@ -477,8 +477,8 @@ var CyclerList = GObject.registerClass({
 var CyclerPopup = GObject.registerClass(
 class CyclerPopup extends SwitcherPopup.SwitcherPopup {
     _init() {
-        if (new.target === CyclerPopup)
-            throw new TypeError('Cannot instantiate abstract class ' + new.target.name);
+        if (this.constructor.name === CyclerPopup.prototype.constructor.name)
+            throw new TypeError(`Cannot instantiate abstract class ${this.constructor.name}`);
 
         super._init();