Fix google analytics setting being ignored

app/views/layouts/_google_analytics.html.haml

 :javascript
   var _gaq = _gaq || [];
-  _gaq.push(['_setAccount', '#{gitlab_config.google_analytics_id}']);
+  _gaq.push(['_setAccount', '#{extra_config.google_analytics_id}']);
   _gaq.push(['_trackPageview']);
 
   (function() {

app/views/layouts/_head.html.haml

@@ -9,7 +9,7 @@
   = csrf_meta_tags
   = include_gon
 
-  = render 'layouts/google_analytics' if gitlab_config.has_key?('google_analytics_id')
+  = render 'layouts/google_analytics' if extra_config.has_key?('google_analytics_id')
 
   -# Atom feed
   - if current_user