[push-api] Rewriting push event handling; allowing data to be optional. (#166)

This is a follow-on to #164.  The event algorithm needed cleaning up, and while I was there, I had to mark PushEvent.data nullable.

Closes #161.
You can view, comment on, or merge this pull request online at:

  https://github.com/w3c/push-api/pull/166

-- Commit Summary --

  * Rewriting push event handling; allowing data to be optional.

-- File Changes --

    M index.html (66)

-- Patch Links --

https://github.com/w3c/push-api/pull/166.patch
https://github.com/w3c/push-api/pull/166.diff

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/push-api/pull/166