imported/w3c/web-platform-tests/html/dom/usvstring-reflection.https.html is consistently failing on mac-wk1 since r264202. History: https://results.webkit.org/?suite=layout-tests&test=imported%2Fw3c%2Fweb-platform-tests%2Fhtml%2Fdom%2Fusvstring-reflection.https.html
<rdar://problem/65335357>
Diff: -FAIL RTCDataChannel.send: unpaired surrogate codepoint should be replaced with U+FFFD. pc1.createDataChannel is not a function. (In 'pc1.createDataChannel('')', 'pc1.createDataChannel' is undefined) +FAIL RTCDataChannel.send: unpaired surrogate codepoint should be replaced with U+FFFD. promise_test: Unhandled rejection with value: object "TypeError: undefined is not an object (evaluating 'options.negotiated')"
Committed r264221: <https://trac.webkit.org/changeset/264221>