Add a screencast indicator for when we're recording

This will replace the indicator painted on the stage right now.

This unfortunately does not work for the recorder triggered by the
keybinding -- we'll simply replace the in-shell code with a keybinding
powered by gnome-settings-daemon.

js/ui/status/screencast.js

@@ -0,0 +1,26 @@
+// -*- mode: js; js-indent-level: 4; indent-tabs-mode: nil -*-
+
+const Lang = imports.lang;
+
+const Main = imports.ui.main;
+const PanelMenu = imports.ui.panelMenu;
+
+const Indicator = new Lang.Class({
+    Name: 'ScreencastIndicator',
+    Extends: PanelMenu.SystemIndicator,
+
+    _init: function() {
+        this.parent();
+
+        this._indicator = this._addIndicator();
+        this._indicator.icon_name = 'media-record-symbolic';
+        this._indicator.add_style_class_name('screencast-indicator');
+        this._sync();
+
+        Main.screencastService.connect('updated', Lang.bind(this, this._sync));
+    },
+
+    _sync: function() {
+        this._indicator.visible = Main.screencastService.isRecording;
+    },
+});