[giow] (3) Refactor the timer code to match current practice in WebKit, Gecko, and Blink (the ones whose source I could examine)
Fixing https://www.w3.org/Bugs/Public/show_bug.cgi?id=22631
Affected topics: HTML

git-svn-id: http://svn.whatwg.org/webapps@8095 340c8d12-0b0e-0410-8428-c7bf67bfef74