Move restacking handling from WorkspacesView to WorkspacesDisplay

Moving the base tracking of restacking to WorkspacesDisplay will allow
us to use it to update stacking in the workspace thumbnails as well as
in the main workspaces.

https://bugzilla.gnome.org/show_bug.cgi?id=640996

js/ui/workspacesView.js

@@ -77,7 +77,6 @@ WorkspacesView.prototype = {
         this._overviewShowingId =
             Main.overview.connect('showing',
                                  Lang.bind(this, function() {
-                this._onRestacked();
                 for (let w = 0; w < this._workspaces.length; w++)
                     this._workspaces[w].zoomToOverview();
         }));
@@ -99,9 +98,6 @@ WorkspacesView.prototype = {
         this._switchWorkspaceNotifyId =
             global.window_manager.connect('switch-workspace',
                                           Lang.bind(this, this._activeWorkspaceChanged));
-        this._restackedNotifyId =
-            global.screen.connect('restacked',
-                                  Lang.bind(this, this._onRestacked));
 
         this._itemDragBeginId = Main.overview.connect('item-drag-begin',
                                                       Lang.bind(this, this._dragBegin));
@@ -207,15 +203,7 @@ WorkspacesView.prototype = {
         return this._workspaces[0].scale;
     },
 
-    _onRestacked: function() {
+    syncStacking: function(stackIndices) {
-        let stack = global.get_window_actors();
-        let stackIndices = {};
-
-        for (let i = 0; i < stack.length; i++) {
-            // Use the stable sequence for an integer to use as a hash key
-            stackIndices[stack[i].get_meta_window().get_stable_sequence()] = i;
-        }
-
         for (let i = 0; i < this._workspaces.length; i++)
             this._workspaces[i].syncStacking(stackIndices);
     },
@@ -502,7 +490,6 @@ WorkspacesView.prototype = {
         this._scrollAdjustment.run_dispose();
         Main.overview.disconnect(this._overviewShowingId);
         global.window_manager.disconnect(this._switchWorkspaceNotifyId);
-        global.screen.disconnect(this._restackedNotifyId);
 
         if (this._timeoutId) {
             Mainloop.source_remove(this._timeoutId);
@@ -824,6 +811,10 @@ WorkspacesDisplay.prototype = {
             global.screen.connect('notify::n-workspaces',
                                   Lang.bind(this, this._workspacesChanged));
 
+        this._restackedNotifyId =
+            global.screen.connect('restacked',
+                                  Lang.bind(this, this._onRestacked));
+
         if (this._itemDragBeginId == 0)
             this._itemDragBeginId = Main.overview.connect('item-drag-begin',
                                                           Lang.bind(this, this._dragBegin));
@@ -836,6 +827,8 @@ WorkspacesDisplay.prototype = {
         if (this._windowDragEndId == 0)
             this._windowDragEndId = Main.overview.connect('window-drag-end',
                                                           Lang.bind(this, this._dragEnd));
+
+        this._onRestacked();
     },
 
     hide: function() {
@@ -845,6 +838,10 @@ WorkspacesDisplay.prototype = {
             global.screen.disconnect(this._nWorkspacesNotifyId);
             this._nWorkspacesNotifyId = 0;
         }
+        if (this._restackedNotifyId > 0){
+            global.screen.disconnect(this._restackedNotifyId);
+            this._restackedNotifyId = 0;
+        }
         if (this._itemDragBeginId > 0) {
             Main.overview.disconnect(this._itemDragBeginId);
             this._itemDragBeginId = 0;
@@ -870,6 +867,18 @@ WorkspacesDisplay.prototype = {
         }
     },
 
+    _onRestacked: function() {
+        let stack = global.get_window_actors();
+        let stackIndices = {};
+
+        for (let i = 0; i < stack.length; i++) {
+            // Use the stable sequence for an integer to use as a hash key
+            stackIndices[stack[i].get_meta_window().get_stable_sequence()] = i;
+        }
+
+        this.workspacesView.syncStacking(stackIndices);
+    },
+
     _workspacesChanged: function() {
         let oldNumWorkspaces = this._workspaces.length;
         let newNumWorkspaces = global.screen.n_workspaces;