[ServiceWorker] WindowClient.focus() resolves with updated WindowClient. (#599)

This is following the discussion in https://github.com/slightlyoff/ServiceWorker/issues/588

CC @annevk  @jakearchibald 
You can merge this Pull Request by running:

  git pull https://github.com/mounirlamouri/ServiceWorker focus_returns_windowclient

Or you can view, comment on it, or merge it online at:

  https://github.com/slightlyoff/ServiceWorker/pull/599

-- Commit Summary --

  * WindowClient.focus() resolves with updated WindowClient.

-- File Changes --

    M spec/service_worker/index.html (2)

-- Patch Links --

https://github.com/slightlyoff/ServiceWorker/pull/599.patch
https://github.com/slightlyoff/ServiceWorker/pull/599.diff

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Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/pull/599