window-list: Untrack chrome while in overview

The window list is set up to track the monitor's fullscreen state.
Monitors are never considered in fullscreen while showing the overview,
so if shell's layout manager updates the fullscreen visibility after
we hid the bottom bar, it ends up being visible in the overview.

To avoid this, untrack the actor while the overview is visible.

Closes: https://gitlab.gnome.org/GNOME/gnome-shell-extensions/-/issues/509
Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell-extensions/-/merge_requests/364>
(cherry picked from commit 981e8e42e2)

extensions/window-list/extension.js

@@ -765,10 +765,11 @@ class WindowList extends St.Widget {
         this._menuManager = new PopupMenu.PopupMenuManager(this);
         this._menuManager.addMenu(this._workspaceIndicator.menu);
 
-        Main.layoutManager.addChrome(this, {
+        const chromeOptions = {
             affectsStruts: true,
             trackFullscreen: true,
-        });
+        };
+        Main.layoutManager.addChrome(this, chromeOptions);
         Main.uiGroup.set_child_above_sibling(this, Main.layoutManager.panelBox);
         Main.ctrlAltTabManager.addGroup(this, _('Window List'), 'start-here-symbolic');
 
@@ -805,10 +806,12 @@ class WindowList extends St.Widget {
 
         Main.overview.connectObject(
             'showing', () => {
+                Main.layoutManager.untrackChrome(this);
                 this.hide();
                 this._updateKeyboardAnchor();
             },
             'hidden', () => {
+                Main.layoutManager.trackChrome(this);
                 this.visible = !this._monitor.inFullscreen;
                 this._updateKeyboardAnchor();
             }, this);