Yeah, that file is using:
<script src='../../resources/testharness.js'></script>
Upstream can just have "/resources/testharness.js". I don't know if it's the single-quotes or the ../../ that's confusing the import. ISTM that both should be supported, but obviously not...
Ah yes, this is due to our absolute path URL rewriting (we don't rewrite relative paths to resources - maybe we should, /cc tkent).
It looks like it's not easy to update an in-progress WPT import so I'll proceed with landing my import with these tests skipped, then we can do another that unskips them to resolve this bug.
Comment 1 by rbyers@chromium.org
, Jun 23 2016