[extensions-web] Remove use of Object.keys

[Jasper St. Pierre <jstpierre src gnome org>]

commit 2bee3cfdc6e5bb4b65eab2daeb6d35fded81d9ad
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Wed Nov 9 13:04:31 2011 -0500

    Remove use of Object.keys

 sweettooth/static/js/extensions.js |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/sweettooth/static/js/extensions.js b/sweettooth/static/js/extensions.js
index cd7ae7f..648c6fc 100644
--- a/sweettooth/static/js/extensions.js
+++ b/sweettooth/static/js/extensions.js
@@ -149,7 +149,7 @@ function($, messages, dbusProxy) {
     $.fn.addLocalExtensions = function () {
         var $container = $(this);
         dbusProxy.ListExtensions().done(function(extensions) {
-            if (extensions && Object.keys(extensions).length) {
+            if (extensions && !$.isEmptyObject(extensions)) {
                 var extensionValues = [];
                 for (var uuid in extensions) {
                     extensionValues.push(extensions[uuid]);