service worker: Upstream sandboxed iframe test to WPT.

Bug: 688116, 532855, 486308
Change-Id: I0cda49c9072099fa706988c6a1aa789456af2c1e
Reviewed-on: https://chromium-review.googlesource.com/765564
Reviewed-by: Hiroki Nakagawa <nhiroki@chromium.org>
Commit-Queue: Matt Falkenhagen <falken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#515885}
3 files changed