Upstream service worker prototype test to WPT

Original patch by mike@mikepennisi.com at https://codereview.chromium.org/2933913002/
Updated with new test expectations only.

Original CL description follows:

Recent improvements to the Web Platform Test's `idlharness.js` utility
introduced tests for immutable prototype objects [1] [2].

Update WPT's existing interface tests (and Chromium "expectations"
files) to use `idlharness.js` and remove the Service-Worker-specific
`interfaces.js` utility (which is far less thorough). Refactor tests
across two files to avoid duplicating sub-test names within the same
test.

[1] https://github.com/w3c/web-platform-tests/commit/55f606ec31b88e7ab7689c2ab3e630cfd2348fae
[2] https://github.com/w3c/web-platform-tests/commit/13b0e2d8d609603b0230ba950404ea21c149f0db

BUG=688116

TBR=yukishiino as it was reviewed on https://codereview.chromium.org/2933913002/

Change-Id: Ic75c68e7a9daafda5d6f00b2bd1bc8ed318fe907
Reviewed-on: https://chromium-review.googlesource.com/598829
Reviewed-by: Matt Falkenhagen <falken@chromium.org>
Commit-Queue: Matt Falkenhagen <falken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#492168}
12 files changed