[gnome-shell] appDisplay: Do not bind popdown call to grabHelper onUngrab

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

commit e641547ddf2c2afb42b4f2d3f250d84e1463a710
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Thu Feb 4 17:37:02 2021 +0100

    appDisplay: Do not bind popdown call to grabHelper onUngrab
    
    grabHelper is passing a boolean argument to onUngrab() callback function
    and since commit 1acbdcc9b3b0 we'd end up adding it to to the callback list or
    we'd try to invoke it:
    
     (gnome-shell:3490851): Gjs-CRITICAL **: 17:19:20.460: JS ERROR:
      TypeError: func is not a function
      onComplete/<@/media/M2/GNOME/gnome-shell/js/ui/appDisplay.js:2407:56
      onComplete@/media/M2/GNOME/gnome-shell/js/ui/appDisplay.js:2407:40
      _makeEaseCallback/<@/media/M2/GNOME/gnome-shell/js/ui/environment.js:85:13
      _easeActor/<@/media/M2/GNOME/gnome-shell/js/ui/environment.js:170:64
    
    Use an arrow function so that we can control the parameters we pass
    to popdown.
    
    Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1635>

 js/ui/appDisplay.js | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/js/ui/appDisplay.js b/js/ui/appDisplay.js
index 2d81a85164..69b4d0fff5 100644
--- a/js/ui/appDisplay.js
+++ b/js/ui/appDisplay.js
@@ -2574,8 +2574,10 @@ var AppFolderDialog = GObject.registerClass({
         if (this._isOpen)
             return;
 
-        this._isOpen = this._grabHelper.grab({ actor: this,
-                                               onUngrab: this.popdown.bind(this) });
+        this._isOpen = this._grabHelper.grab({
+            actor: this,
+            onUngrab: () => this.popdown(),
+        });
 
         if (!this._isOpen)
             return;