[ES6 modules] WPT: mark error test cases as flaky

The web platform tests testing module script errors are not deterministic
until we have the new algorithm being proposed at HTML PRs below:
- https://github.com/whatwg/html/pull/2971
- https://github.com/whatwg/html/pull/2991

This CL marks the test as flaky until we land the new algorithm.

TBR=hiroshige@chromium.org

Bug: 767093, 763597
Change-Id: I9ef17f2ae6dc51acbef4dbab1f7f7c7438d17eb7
Reviewed-on: https://chromium-review.googlesource.com/676403
Reviewed-by: Kouhei Ueno <kouhei@chromium.org>
Commit-Queue: Kouhei Ueno <kouhei@chromium.org>
Cr-Commit-Position: refs/heads/master@{#503304}
1 file changed