[webcomponents] Extend the slotting algorithm so that a slot can select an element which doesn't have slot attribute. (#343)

I am afraid that component authors would complain when they find that shadow host's children should always have a slot attribute, after shipping v1.

I don't have an intention to include this feature to v1. Let me file an issue here with v2 label, so that users can know that we are aware of this concern.


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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/issues/343