Fix WPT execution of tentative fullscreen options test

Followup after inadequate fix in http://crrev.com/c/4525083
1) Reorder script tags to fix driver context error
  "Tried to run in a non-testharness window without a call to set_test_context"
2) Move files to https for secure context requirement
  "invalid argument: feature cannot be used in insecure context"
3) Update ini to expect PASS in chrome
4) Cleanup: use assert_true and update help URL

This test now passes on a local WPT checkout with "wpt run chrome".

Bug: 1022988
Change-Id: Ib1a23f794ac8e0b7c7145fb50e362a180e6687e9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4545785


Auto-Submit: Mike Wasserman <msw@chromium.org>
Reviewed-by: Brad Triebwasser <btriebw@chromium.org>
Commit-Queue: Brad Triebwasser <btriebw@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1145703}