[webcomponents] Add metrics link in Shadow DOM v1 migration plan. (#342)

@hayatoito PTAL
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/webcomponents/pull/342

-- Commit Summary --

  * Add metrics link in Shadow DOM v1 migration plan.

-- File Changes --

    M proposals/shadow-dom-v1-in-blink.md (3)

-- Patch Links --

https://github.com/w3c/webcomponents/pull/342.patch
https://github.com/w3c/webcomponents/pull/342.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/webcomponents/pull/342