MSE spec and test status

All,

We have made excellent progress this week on closing down all but 1 MSE
spec issue, and that one issue (#74) is not blocking any PR or REC
transition.
Work is still in-progress on updating the MSE web-platform-test suite to
conform to recent changes in the spec, increased coverage of the spec, and
integrating submissions from downstream UA tests that similarly have
adapted coverage and conformance to recent changes in the spec.

Details of progress this week (from my perspective):

*MSE spec*

   - Updated and landed my https://github.com/w3c/media-source/pull/143 to
   fix https://github.com/w3c/media-source/issues/99
   - Updated and landed my https://github.com/w3c/media-source/pull/146 to
   fix https://github.com/w3c/media-source/issues/104
   - Filed issue, prepared and landed my https://github.com/w3c/media-
   source/pull/150 to fix https://github.com/w3c/media-source/issues/149
   - Filed issue, prepared and landed my https://github.com/w3c/media-
   source/pull/153 to fix https://github.com/w3c/media-source/issues/152
   - Prepared, synced w/sandersd@ <https://teams.googleplex.com/sandersd>,
   updated, and landed my https://github.com/w3c/media-source/pull/151 to
   fix https://github.com/w3c/media-source/issues/147
   - Iterated on two proposals, landed my https://github.com/w3c/media-
   source/pull/154 to fix https://github.com/w3c/media-source/issues/124
      - Prepped an option for Plan C: https://github.com/w3c/media-
      source/pull/148
      - MSFT and FF pushed back on Plan C, leading me to rethink
      <https://github.com/w3c/media-source/pull/148#issuecomment-240599738>.
      - Prepped an option for Plan B: https://github.com/w3c/media-
      source/pull/154
      - Filed crbug 639144 <http://crbug/639144> to get to compliance w/
      the spec change in Plan B
   - *Currently, only a non-blocking bytestream registry rehoming spec
   issue remains open (#74), @plehegar to fix this later.*

------------------------------

*MSE Test suite (in-progress)*

   - Stamped Chromium+W3C license onto media-source/*.{html,js} files that
   originated in Blink <https://github.com/w3c/web-platform-tests/pull/3498>
   - review and merge in pending test suite PRs: francois' and plh's changes
      - tidoust's: https://github.com/w3c/web-platform-tests/pulls?q=is%
      3Aopen+is%3Apr+label%3Amedia-source+author%3Atidoust
      <https://github.com/w3c/web-platform-tests/pulls?q=is%3Aopen+is%3Apr+label%3Amedia-source+author%3Atidoust>
         - @tidoust's https://github.com/w3c/web-platform-tests/pull/3182:
         I addressed my review comments and landed it as
         https://github.com/w3c/web-platform-tests/pull/3497
         <https://github.com/w3c/web-platform-tests/pull/3497>
            - I filed new crbug 639151 <http://crbug/639151> to fix the
            Chrome compliance errors encountered in two of the new
sub-tests in this PR
         - @tidoust's https://github.com/w3c/web-platform-tests/pull/3187:
         I reviewed and landed it
         - @tidoust's https://github.com/w3c/web-platform-tests/pull/3215:
         I reviewed and landed it
            - crbug 633669 <http://crbug/633669> tracks the multiple MSE
            IDL harness test failures in Chrome
         - @tidoust's https://github.com/w3c/web-platform-tests/pull/3223:
         I reviewed and landed it
         - @tidoust's https://github.com/w3c/web-platform-tests/pull/3224:
         I reviewed and landed it
            - crbug 607372 <http://crbug/607372> tracks the known issue
            exposed in one of the new sub-tests in this PR where,
though we force
            sequence behavior, we don't reflect it in the mode attribute, for
            bytestreams with generate_timestamps flag true
         - *in progress*: @tidoust's https://github.com/w3c/web-
         platform-tests/pull/3233:
            - needs adjustment (especially relative to "Plan B"
            https://github.com/w3c/media-source/pull/154
            <https://github.com/w3c/media-source/pull/154>, assuming #154
            lands soon)
         - TODO review more of @tidoust's PRs: 3239, 3264
         - TODO review @plehegar's PRs: 3205-07
      -

   TODO:
   - resolve merge conflict of the following (vs already upstreamed MOZ and
      not-yet-upstreamed Chromium https://codereview.chromium.org/2102323002
      )
         - @tidoust's https://github.com/w3c/web-platform-tests/pull/3231/
         - @tidoust's https://github.com/w3c/web-platform-tests/pull/3232/
      - determine if any of mozilla's changes are already covered by
      francois' changes
      - determine if any further changes are required to update the test
      suite


I will continue work on updating the test suite per the items marked
"TODO", above, next week.

--Matt Wolenetz
(I'll resend this same data, with better formatting, if the w3c archiver
doesn't correctly show the intended formatting.)