Bug 860473 part 1.  Root WebIDL dictionary ParseJSON.  r=evilpie, smaug
Bug 860473 part 2.  Root WebIDL dictionary ToObject.  r=evilpie,smaug
Bug 860473 part 3.  Root ErrorResult::ThrowJSException.  r=evilpie,smaug
Bug 860551.  Fix instanceof for prototype-less interface objects to be saner.  r=dzbarsky
Bug 855402.  Don't try to write to the startup cache if there isn't one, and definitely don't start _thinking_ we've written to it.  r=ehsan