[JSC] Clean up Intl option parsing code by introducing intlOption<>
Created attachment 404508 [details] Patch
Created attachment 404510 [details] Patch
Comment on attachment 404510 [details] Patch r=me, this is great!
Created attachment 404534 [details] Patch
compositing/repaint/iframes/compositing-iframe-scroll-repaint.html is failing without this patch recently.
OK, failing tests are failing in buildbot too.
Committed r264500: <https://trac.webkit.org/changeset/264500>
<rdar://problem/65709681>