[giow] (2) Fix bug 18626 and actually do what the previous checkin was trying to do.
Affected topics: HTML

git-svn-id: http://svn.whatwg.org/webapps@7668 340c8d12-0b0e-0410-8428-c7bf67bfef74
[giow] (3) Make MessagePort objects synchronised until they are posted through another port.
Fixing https://www.w3.org/Bugs/Public/show_bug.cgi?id=15063
Affected topics: DOM APIs

git-svn-id: http://svn.whatwg.org/webapps@7669 340c8d12-0b0e-0410-8428-c7bf67bfef74