The loader base path auto-detection doesn't work for _source

[fredck]

If we want CKEDITOR.loader to load things from _source, it'll not work.

This is my TC:

<script type="text/javascript" src="/ckeditor/_source/core/loader.js"></script>
<script type="text/javascript">

CKEDITOR.loader.load( 'core/xml' );
	
</script>

Firebug will show you 404s for the loaded resources.

[fredck]

Fixed with [5860].