Add originating page URL query-param to beacon URL

[GoogleCodeExporter]

This will help sites that want to send all beacons for a page to the same 
physical server as the one that will handle the HTML.

Note that we do send the encoded URL as a post parameter, but the 
load-balancing is much easier to do if it's available as a query-param.


It would be preferable to remove the post-body param and rely solely on the 
query-param for transmitting the URL.  If you don't do this, then I think we'll 
need a new pagespeed.conf option to additionally add the URL as a query-param.  
But if that's easier for some reason then it seems acceptable.

Original issue reported on code.google.com by jmara...@google.com on 8 May 2013 at 7:41