Progressbar demo: Made animated background selector more specific. Fixes #8314 - Theme on animated progressbar remains the same.

(cherry picked from commit cb70a5e)

Author: scottgonzalez

demos/progressbar/animated.html

@@ -10,7 +10,7 @@
 	<script src="../../ui/jquery.ui.progressbar.js"></script>
 	<link rel="stylesheet" href="../demos.css">
 	<style>
-	.ui-progressbar-value { background-image: url(images/pbar-ani.gif); }
+	.ui-progressbar .ui-progressbar-value { background-image: url(images/pbar-ani.gif); }
 	</style>
 	<script>
 	$(function() {