[webcomponents] deepPath's definition is ambiguous when the event path contains a non-Node EventTarget (#432)

We should clarify what happens when an event is fired on an XHR object, etc... Are we going to include all those items in the path that are not Node?  Or does path only contain nodes?

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/issues/432