[gnome-shell/wip/exalm/gestures: 15/16] workspaceAnimation: Use window clones

[Alexander Mikhaylenko <alexm src gnome org>]

commit 7befaf3e10e3a260eca33b4aafbfcd2bed463308
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Thu Jul 4 23:15:15 2019 +0500

    workspaceAnimation: Use window clones
    
    Instead of reparenting windows, clone them. This will allow to properly
    support multi-monitor setups in subsequent commits.
    
    Block window mapping animation while the animation is running to prevent
    new windows appearing during the animation from being visible at the same
    time as their clones.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/605

 js/ui/workspaceAnimation.js | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)
---
diff --git a/js/ui/workspaceAnimation.js b/js/ui/workspaceAnimation.js
index d9732b47b7..c983ef3dae 100644
--- a/js/ui/workspaceAnimation.js
+++ b/js/ui/workspaceAnimation.js
@@ -47,13 +47,17 @@ class WorkspaceGroup extends Clutter.Actor {
         windows = windows.filter(w => this._shouldShowWindow(w.meta_window));
 
         for (let window of windows) {
-            let record = { window,
-                           parent: window.get_parent() };
+            let clone = new Clutter.Clone({ source: window,
+                                            x: window.x,
+                                            y: window.y });
 
-            record.parent.remove_child(window)
-            this.add_child(window);
+            this.add_actor(clone);
+            window.hide();
+
+            let record = { window, clone: clone };
 
             record.windowDestroyId = window.connect('destroy', () => {
+                clone.destroy();
                 this._windows.splice(this._windows.indexOf(record), 1);
             });
 
@@ -66,12 +70,11 @@ class WorkspaceGroup extends Clutter.Actor {
             let w = this._windows[i];
 
             w.window.disconnect(w.windowDestroyId);
-            this.remove_child(w.window);
-            w.parent.add_child(w.window)
+            w.clone.destroy();
 
-            if (w.window.get_meta_window().get_workspace() !=
+            if (w.window.get_meta_window().get_workspace() ==
                 global.workspace_manager.get_active_workspace())
-                w.window.hide();
+                w.window.show();
         }
 
         this._windows = [];