[webcomponents] [Custom Elements] Write-up proposal for using a "state object" (#287)

State object to allow the developer to see a consistent "state" at constructor time (and possibly lifecycle callbacks as well) to enable consistency between upgrade and non-upgrade scenarios without having to do a fancy dance to remove attrs, children, etc. and then re-add.

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/issues/287