[gnome-shell/gnome-3-32] keyboard: Destroy old layout actors when regenerating keyboard groups

[Florian Müllner <fmuellner src gnome org>]

commit 5100458c1bc00ba14b7beabaed98c872ac8d7402
Author: Carlos Garnacho <carlosg gnome org>
Date:   Tue Apr 30 12:08:25 2019 +0000

    keyboard: Destroy old layout actors when regenerating keyboard groups
    
    We were cleaning up self._groups, but the actors for all previous
    groups/layers/modes would remain attached to the aspect container,
    simply hidden.
    
    Under some circumstances this can really make the amount of actors
    in the shell stage to quickly ramp up, it's not just a "leak" but
    also has potential side effects on performance.
    
    We should destroy all child actors of this._aspectContainer, except
    the static ones (emoji and keypad).
    
    While at it, fix this._groups re-initialization, as it's actually an
    object, not an array.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/523
    Closes?: https://gitlab.gnome.org/GNOME/mutter/issues/556
    
    
    (cherry picked from commit ed999ce92693b8f1ab4040444a3e6e380e7b4475)

 js/ui/keyboard.js | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)
---
diff --git a/js/ui/keyboard.js b/js/ui/keyboard.js
index 8dc1b306f..c4ac72d1d 100644
--- a/js/ui/keyboard.js
+++ b/js/ui/keyboard.js
@@ -1470,7 +1470,12 @@ var Keyboard = class Keyboard {
     }
 
     _onKeyboardGroupsChanged(keyboard) {
-        this._groups = [];
+        let nonGroupActors = [this._emojiSelection.actor, this._keypad.actor];
+        this._aspectContainer.get_children().filter(c => !nonGroupActors.includes(c)).forEach(c => {
+            c.destroy();
+        });
+
+        this._groups = {};
         this._onGroupChanged();
     }