I suppose you are opening this page not via webserver, but directly from filesystem. If so, never do that way. There can be various restrictions with AJAX, canvas, etc.
In your example you're trying to load outer scripts with protocol relative URLs.
In case of opening page from filesystem, URLs are being transformed into file://...
format.
To solve this problem you should use a webserver. If you can't use it for some reasons, add http:
to the beginning of the outer URLs, so it will be:
http://ajax.googleapis.com/ajax/libs/angularjs/1.2.7/angular.min.js
instead of
//ajax.googleapis.com/ajax/libs/angularjs/1.2.7/angular.min.js