This error is very cryptic and hides what the real error is.
In my case, it was issue of Cross Domain Resource Sharing. In simple english, AJAX requests can only happen on the same domain (for security reasons) unless your server is configured to support it.
You can confirm this thing by running chromium as:
Solution is to just use same domain in both config.js and the palce where Kibana3 is hosted. Easy ehh, not the error though.