messageTray: Don't set _notificationRemoved if destroyed notification is queued

When the user clears all notifications from the notification menu UI, it's
possible for a queued notification to be destroyed after the currently displayed
notification. The removal of the currently displayed notification is not
processed until the notification menu is closed (due to `this._bannerBlocked`).
By then, it's possible that `_notificationRemoved` has already been overwritten
when `_onNotificationDestroy` is invoked with another (queued) notification.

This eventually results in a notification banner that cannot be removed by the
user as the notification object needed to do so has already been destroyed.

Fix this by only assigning to `_notificationRemoved` if `this._notification ==
notification`.

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2736>

1 files changed, 2 insertions, 3 deletions

diff --git a/js/ui/messageTray.js b/js/ui/messageTray.js
index e001f2202..1edd932f6 100644
--- a/js/ui/messageTray.js
+++ b/js/ui/messageTray.js
@@ -1006,9 +1006,8 @@ var MessageTray = GObject.registerClass({
     }
 
     _onNotificationDestroy(notification) {
-        this._notificationRemoved = this._notification === notification;
-
-        if (this._notificationRemoved) {
+        if (this._notification === notification) {
+            this._notificationRemoved = true;
             if (this._notificationState === State.SHOWN ||
                 this._notificationState === State.SHOWING) {
                 this._updateNotificationTimeout(0);