Port client side code to GDBus

This continues the series of patches for GDBus porting, affecting
all code that accesses remote DBus objects. This includes modemManager,
automount, autorun (for the hotplug sniffer), calendar, network (for
nm-applet only), power, scripting (for perf monitor interface)

https://bugzilla.gnome.org/show_bug.cgi?id=648651

js/ui/magnifierDBus.js

@@ -1,6 +1,7 @@
 // -*- mode: js; js-indent-level: 4; indent-tabs-mode: nil -*-
 
 const Gio = imports.gi.Gio;
+const GLib = imports.gi.GLib;
 const Main = imports.ui.main;
 
 const MAG_SERVICE_NAME = 'org.gnome.Magnifier';

js/ui/status/network.js

@@ -1,6 +1,7 @@
 // -*- mode: js; js-indent-level: 4; indent-tabs-mode: nil -*-
 const ByteArray = imports.byteArray;
 const GLib = imports.gi.GLib;
+const Gio = imports.gi.Gio;
 const GObject = imports.gi.GObject;
 const Lang = imports.lang;
 const Mainloop = imports.mainloop;

js/ui/status/power.js

@@ -1,6 +1,7 @@
 // -*- mode: js; js-indent-level: 4; indent-tabs-mode: nil -*-
 
 const Gio = imports.gi.Gio;
+const GLib = imports.gi.GLib;
 const Lang = imports.lang;
 const Mainloop = imports.mainloop;
 const Shell = imports.gi.Shell;

js/ui/userMenu.js

@@ -309,7 +309,9 @@ IMStatusChooserItem.prototype = {
         this._setComboboxPresence(presence);
 
         if (!this._sessionPresenceRestored) {
-            this._sessionStatusChanged(this._presence.status);
+            this._presence.connectSignal('StatusChanged', Lang.bind(this, function (proxy, senderName, [status]) {
+		this._sessionStatusChanged(status);
+	    }));
             return;
         }
 
@@ -469,6 +471,10 @@ UserMenuButton.prototype = {
         this._idleIcon = new St.Icon({ icon_name: 'user-idle',
                                        style_class: 'popup-menu-icon' });
 
+        this._presence.connectSignal('StatusChanged', Lang.bind(this, function (proxy, senderName, [status]) {
+	    this._updateSwitch(status);
+	}));
+
         this._accountMgr.connect('most-available-presence-changed',
                                   Lang.bind(this, this._updatePresenceIcon));
         this._accountMgr.prepare_async(null, Lang.bind(this,