Created attachment 809214 [details] [diff] [review] Patch v1 The parsing fails because the version of the IDL parser we have doesn't support default arguments. Since these aren't actually used, I'm just going to comment them out until we update the IDL parser. I also wrapped the parsing in a setup call, so we won't have this silently happen again (upstreamed as <https://github.com/w3c/web-platform-tests/pull/351>).
Comment on attachment 809214 [details] [diff] [review] Patch v1 >- void collapse(optional boolean toStart = false); >+ void collapse(optional boolean toStart /* = false */); Isn't it a read-only copy of the upstream? :)