From db2245d60bff3c581b8097804d97dfadb35c8ebf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Florian=20M=C3=BCllner?= <fmuellner@gnome.org>
Date: Mon, 9 Jul 2018 12:19:00 +0200
Subject: [PATCH] workspaceThumbnail: Don't keep stale clones in list

If a clone gets destroyed before the corresponding MetaWindow is
removed from the workspace, we will still find it in the list of
clones and try to destroy it again. Avoid the resulting warnings
by updating the list of clones immediately when a clone is destroyed.

https://bugzilla.gnome.org/show_bug.cgi?id=791233
---
 js/ui/workspaceThumbnail.js | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/js/ui/workspaceThumbnail.js b/js/ui/workspaceThumbnail.js
index aff2b4abc..381169ea6 100644
--- a/js/ui/workspaceThumbnail.js
+++ b/js/ui/workspaceThumbnail.js
@@ -372,16 +372,9 @@ var WorkspaceThumbnail = new Lang.Class({
     },
 
     _doRemoveWindow(metaWin) {
-        // find the position of the window in our list
-        let index = this._lookupIndex (metaWin);
-
-        if (index == -1)
-            return;
-
-        let clone = this._windows[index];
-        this._windows.splice(index, 1);
-
-        clone.destroy();
+        let clone = this._removeWindowClone(metaWin);
+        if (clone)
+            clone.destroy();
     },
 
     _doAddWindow(metaWin) {
@@ -533,6 +526,9 @@ var WorkspaceThumbnail = new Lang.Class({
         clone.connect('drag-end', () => {
             Main.overview.endWindowDrag(clone.metaWindow);
         });
+        clone.actor.connect('destroy', () => {
+            this._removeWindowClone(clone.metaWindow);
+        });
         this._contents.add_actor(clone.actor);
 
         if (this._windows.length == 0)
@@ -545,6 +541,16 @@ var WorkspaceThumbnail = new Lang.Class({
         return clone;
     },
 
+    _removeWindowClone(metaWin) {
+        // find the position of the window in our list
+        let index = this._lookupIndex (metaWin);
+
+        if (index == -1)
+            return null;
+
+        return this._windows.splice(index, 1).pop();
+    },
+
     activate(time) {
         if (this.state > ThumbnailState.NORMAL)
             return;