From discussion in http://forum.piwik.org/index.php?showtopic=217
Depends on: #409
On second thought, this doesn't depend on 409, but the client (piwik.js) needs to know/reconstruct the 3rd party cookie name.
We do need #408 fixed (possibly in conjunction with this ticket).
A first party cookie set by the client is sent as a URL param, eg PK_FPC (we could have a default and allow it to be set, ala cookie_name on the server).
Since first- vs third-party depends on whether Piwik is hosted on the same domain as the site being tracked, I'll refer to the current implementation as "legacy cookies".
User stories:
Need to add documentation re: P3P policy for IE6+.
Building on the new piwik.js, the implementation stalled on how the client would initialize the fpc (first time). Theoretically, we could implement the JavaScript equivalent of md5(uniqid(rand(), true)) /* i.e., idvisitor in the current cookie implementation */
See http://phpjs.org for JavaScript equivalents of various PHP functions.
Dependencies:
Rolling in the requirements of this ticket into #409