[giow] (2) Try to make ordering of media events even more well-defined.
Fixing https://www.w3.org/Bugs/Public/show_bug.cgi?id=18570
Affected topics: Video and Audio

git-svn-id: http://svn.whatwg.org/webapps@7743 340c8d12-0b0e-0410-8428-c7bf67bfef74
[e] (0) Cleanup
Affected topics: DOM APIs, HTML, Video and Audio

git-svn-id: http://svn.whatwg.org/webapps@7744 340c8d12-0b0e-0410-8428-c7bf67bfef74