docs: Update google analytics code

Change-Id: I4807745d13174c373f65c028dd4061c2e02d0280
diff --git a/docs/named_data_theme/named_data_footer-with-analytics.html.in b/docs/named_data_theme/named_data_footer-with-analytics.html.in
index b05c1f2..68a4a9d 100644
--- a/docs/named_data_theme/named_data_footer-with-analytics.html.in
+++ b/docs/named_data_theme/named_data_footer-with-analytics.html.in
@@ -18,20 +18,15 @@
 </small></address>
 <!--END !GENERATE_TREEVIEW-->
 
-<script type="text/javascript">
+<script>
+  (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
+  (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
+  m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
+  })(window,document,'script','//www.google-analytics.com/analytics.js','ga');
 
-  var _gaq = _gaq || [];
-  _gaq.push(['_setAccount', '@GOOGLE_ANALYTICS@']);
-  _gaq.push(['_trackPageview']);
-
-  (function() {
-    var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;
-    ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
-    var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);
-  })();
+  ga('create', '@GOOGLE_ANALYTICS@', 'auto');
+  ga('send', 'pageview');
 </script>
 
-<script type="text/javascript">
-</script>
 </body>
 </html>