remoteMenu: Add support for submenu items

Wrap new GtkMenuTracker API that adds an easy way to bind to
tracker items, and use it to add back support for submenus.
This also adds support for a submenu feature that we didn't
have support for before, action namespaces.

https://bugzilla.gnome.org/show_bug.cgi?id=700257

js/ui/remoteMenu.js

@@ -25,6 +25,9 @@ function _insertItem(menu, trackerItem, position) {
     if (trackerItem.get_is_separator()) {
         let mapper = new RemoteMenuSeparatorItemMapper(trackerItem);
         item = mapper.menuItem;
+    } else if (trackerItem.get_has_submenu()) {
+        let mapper = new RemoteMenuSubmenuItemMapper(trackerItem);
+        item = mapper.menuItem;
     } else {
         let mapper = new RemoteMenuItemMapper(trackerItem);
         item = mapper.menuItem;
@@ -57,6 +60,34 @@ const RemoteMenuSeparatorItemMapper = new Lang.Class({
     },
 });
 
+const RemoteMenuSubmenuItemMapper = new Lang.Class({
+    Name: 'RemoteMenuSubmenuItemMapper',
+
+    _init: function(trackerItem) {
+        this._trackerItem = trackerItem;
+        this.menuItem = new PopupMenu.PopupSubMenuMenuItem('');
+        this._trackerItem.connect('notify::label', Lang.bind(this, this._updateLabel));
+        this._updateLabel();
+
+        this._tracker = Shell.MenuTracker.new_for_item_submenu(this._trackerItem,
+                                                               _insertItem.bind(null, this.menuItem.menu),
+                                                               _removeItem.bind(null, this.menuItem.menu));
+
+        this.menuItem.connect('destroy', function() {
+            trackerItem.run_dispose();
+        });
+    },
+
+    destroy: function() {
+        this._tracker.destroy();
+        this.parent();
+    },
+
+    _updateLabel: function() {
+        this.menuItem.label.text = stripMnemonics(this._trackerItem.label);
+    },
+});
+
 const RemoteMenuItemMapper = new Lang.Class({
     Name: 'RemoteMenuItemMapper',
 

src/shell-menu-tracker.c

@@ -106,6 +106,33 @@ shell_menu_tracker_new (GtkActionObservable        *observable,
   return tracker;
 }
 
+ShellMenuTracker *
+shell_menu_tracker_new_for_item_submenu (GtkMenuTrackerItem         *item,
+                                         ShellMenuTrackerInsertFunc  insert_func,
+                                         gpointer                    insert_user_data,
+                                         GDestroyNotify              insert_notify,
+                                         ShellMenuTrackerRemoveFunc  remove_func,
+                                         gpointer                    remove_user_data,
+                                         GDestroyNotify              remove_notify)
+{
+  ShellMenuTracker *tracker = g_slice_new0 (ShellMenuTracker);
+
+  tracker->ref_count = 1;
+  tracker->insert_func = insert_func;
+  tracker->insert_user_data = insert_user_data;
+  tracker->insert_notify = insert_notify;
+  tracker->remove_func = remove_func;
+  tracker->remove_user_data = remove_user_data;
+  tracker->remove_notify = remove_notify;
+
+  tracker->tracker = gtk_menu_tracker_new_for_item_submenu (item,
+                                                            shell_menu_tracker_insert_func,
+                                                            shell_menu_tracker_remove_func,
+                                                            tracker);
+
+  return tracker;
+}
+
 ShellMenuTracker *
 shell_menu_tracker_ref (ShellMenuTracker *tracker)
 {

src/shell-menu-tracker.h

@@ -47,6 +47,14 @@ ShellMenuTracker * shell_menu_tracker_new (GtkActionObservable        *observabl
                                            ShellMenuTrackerRemoveFunc  remove_func,
                                            gpointer                    remove_user_data,
                                            GDestroyNotify              remove_notify);
+ShellMenuTracker * shell_menu_tracker_new_for_item_submenu (GtkMenuTrackerItem         *item,
+                                                            ShellMenuTrackerInsertFunc  insert_func,
+                                                            gpointer                    insert_user_data,
+                                                            GDestroyNotify              insert_notify,
+                                                            ShellMenuTrackerRemoveFunc  remove_func,
+                                                            gpointer                    remove_user_data,
+                                                            GDestroyNotify              remove_notify);
+
 ShellMenuTracker * shell_menu_tracker_ref (ShellMenuTracker *tracker);
 void shell_menu_tracker_unref (ShellMenuTracker *tracker);
 void shell_menu_tracker_destroy (ShellMenuTracker *tracker);