[Web Timing] UserTiming

Hi All,

I've added the first draft copy of the UserTiming [1] spec to webperf repository.  The problem with using new Date() to capture timing information for custom scenarios relies on the accuracy of the timer within the user agent.

Building on the 1ms precision called out in Navigation Timing,  this specification defines an interface for web applications to capture timing information with a developer supplied name. The user agent captures the time stamp at the point and time specified in the code executing in the user agent.

[1] http://dvcs.w3.org/hg/webperf/raw-file/tip/specs/UserTiming/Overview.htm<http://dvcs.w3.org/hg/webperf/raw-file/tip/specs/UserTiming/Overview.html#DOMPerformanceTimingList>

Regards,
Anderson Quach
IE Program Manager