[webcomponents] Make ShadowRoot objects use DocumentFragment object's host concept (#430)

Otherwise various DOM mutation algorithms will not throw.

https://dom.spec.whatwg.org/#concept-documentfragment-host

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/issues/430

Received on Wednesday, 9 March 2016 15:41:29 UTC