Necessity of an additional state to indicate a session was resumed

[mfoltzgoogle]

From http://webscreens.github.io/presentation-api/#open-questions:

Do we need an additional state like resumed in order to identify resumed session? It seems that this could be handled on the page level. The opener page could ask the presentation page whether it is "new" or "resumed".

[mfoltzgoogle]

The current specification provides two different mechanisms for obtaining a PresentationSession: a new session via startSession() or connection to an existing session via joinSession(). Therefore the controlling page should be able to identify whether the session was started or resumed.

[avayvod]

I think this issue may have covered the case when the page connected to the existing presentation via startSession()? The presentation could communicate that to the controller page though so I don't think we need to change the spec anyway.