[giow] (2) Flesh out how rendering happens in the event loop. This also defines requestAnimationFrame() and obsoletes the 'Timing control for script-based animations' spec (by request of that spec's editors)
Fixing https://www.w3.org/Bugs/Public/show_bug.cgi?id=26839
Affected topics: DOM APIs, HTML

git-svn-id: https://svn.whatwg.org/webapps@8849 340c8d12-0b0e-0410-8428-c7bf67bfef74