[giow] (3) Provide hook for pagevis. Correctly return false for event.persisted in pagehide. Define one of the variables in an algorithm.
Affected topics: HTML, HTML Syntax and Parsing

git-svn-id: http://svn.whatwg.org/webapps@8160 340c8d12-0b0e-0410-8428-c7bf67bfef74