The spec for MediaKeyNeededEvent and MediaKeyMessageEvent definitions [1] should explicitly define a mapping from named entries in MediaKey*EventInit to MediaKey*Event.

i.e. it should be explicit what happens when script does this:

  var ev = new MediaKeyMessageEvent("something", {});

After that, what will ev.message be and why?

We also need to define what happens when parameters are empty; like in the example above, what's the default value of the initData? null presumably. And the other fields?

Also, we should define that the MediaKeyNeededEvent.initData and MediaKeyMessageEvent.message attributes are copied from their respective InitDict params during initialization. Otherwise if a reference to the InitDict's initData array is stored in the MediaKeyNeededEvent, other script could change the initData at any time, causing all kinds of problems.


[1] https://dvcs.w3.org/hg/html-media/raw-file/default/encrypted-media/encrypted-media.html#event-definitions