FIX: apply s3 cdn to client side assets

app/views/common/_discourse_javascript.html.erb

@@ -40,6 +40,12 @@
   Discourse.set('assetVersion','<%= Discourse.assets_digest %>');
   Discourse.Session.currentProp("disableCustomCSS", <%= loading_admin? %>);
   Discourse.HighlightJSPath = <%= HighlightJs.path.inspect.html_safe %>;
+  <%- if SiteSetting.enable_s3_uploads %>
+    <%- if SiteSetting.s3_cdn_url.present? %>
+      Discourse.S3CDN = '<%= SiteSetting.s3_cdn_url %>';
+    <%- end %>
+    Discourse.S3BaseUrl = '<%= Discourse.store.absolute_base_url %>';
+  <%- end %>
 </script>
 
 <%= script 'browser-update' %>