Upstream service wrkr "registration" tests to WPT

**registration**

This test file was upstreamed to the Web Platform Tests project in
Chromium commit e46007715a723c2219f49db6199f1af09cbbc7db, but the
associated "expectations" file was mistakenly persisted. Remove the
expectations file.

**registration-end-to-end**

The version of this test in the Chromium source tree is equivalent to
the version available in the Web Platform Tests project. Remove the
Chromium version.

**registration-events**

The version of this test in the Chromium source tree is equivalent to
the version available in the Web Platform Tests project. Remove the
Chromium version.

**registration-service-worker-attributes**

The version defined by the Chromium project is more strict in that it
does not allow workers to transition between states before Promise
resolution microtasks have been executed. Because any such transition
would be in violation of the service workers specification, the
additional strictness is preferable.

Remove the logic that relaxes the WPT version of this test, and remove
the Chromium test file entirely.

BUG=688116
R=falken@chromium.org

Review-Url: https://codereview.chromium.org/2893743003
Cr-Commit-Position: refs/heads/master@{#472821}
7 files changed