R=rossberg BUG= Review URL: https://codereview.chromium.org/1823973002 Cr-Commit-Position: refs/heads/master@{#35020}
Both of them shipped in Chrome 49 without incident. Also move relevant tests from harmony/ to es6/. Review URL: https://codereview.chromium.org/1815773002 Cr-Commit-Position: refs/heads/master@{#34964}