[gnome-shell-extensions/wip/fix-window-list-leak] window-list: Stop monitoring drag operation if window disappears

[Ray Strode <halfline src gnome org>]

commit 315c92e00c9cd9be895bd84d1de8d8009ee1e639
Author: Ray Strode <rstrode redhat com>
Date:   Tue Nov 24 00:24:55 2020 -0500

    window-list: Stop monitoring drag operation if window disappears
    
    If a user is in the middle of a drag in the window list when the
    window associated with that drag gets destroyed, the drag monitor
    gets leaked.
    
    Later when the drag motion is processed, this spew goes to the log
    
    clutter_actor_contains: assertion 'CLUTTER_IS_ACTOR (self)' failed
    
    This commit fixes the spew and the leak by ensuring any pending
    drag monitoring is disabled when the window is destroyed.

 extensions/window-list/extension.js | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)
---
diff --git a/extensions/window-list/extension.js b/extensions/window-list/extension.js
index 616bec6..a7a7a5e 100644
--- a/extensions/window-list/extension.js
+++ b/extensions/window-list/extension.js
@@ -786,9 +786,9 @@ class WindowList extends St.Widget {
             });
 
         this._dragBeginId = Main.xdndHandler.connect('drag-begin',
-            this._onDragBegin.bind(this));
+            this._monitorDrag.bind(this));
         this._dragEndId = Main.xdndHandler.connect('drag-end',
-            this._onDragEnd.bind(this));
+            this._stopMonitoringDrag.bind(this));
         this._dragMonitor = {
             dragMotion: this._onDragMotion.bind(this),
         };
@@ -1016,11 +1016,11 @@ class WindowList extends St.Widget {
         }
     }
 
-    _onDragBegin() {
+    _monitorDrag() {
         DND.addDragMonitor(this._dragMonitor);
     }
 
-    _onDragEnd() {
+    _stopMonitoringDrag() {
         DND.removeDragMonitor(this._dragMonitor);
         this._removeActivateTimeout();
     }
@@ -1094,6 +1094,7 @@ class WindowList extends St.Widget {
 
         global.display.disconnect(this._fullscreenChangedId);
 
+        this._stopMonitoringDrag();
         Main.xdndHandler.disconnect(this._dragBeginId);
         Main.xdndHandler.disconnect(this._dragEndId);