src: support domains with empty labels in i18n

Summary

The domainToUnicode and the domainToASCII could be used in the middle of parsing the origin, and it means the input values could be a non-final domain name label. Then the converter should ignore the UIDNA_ERROR_EMPTY_LABEL error. Since long domain name labels and long domain names are invalid already, it might not need to ignore UIDNA_ERROR_LABEL_TOO_LONG and UIDNA_ERROR_DOMAIN_NAME_TOO_LONG.

Refs:

• http://icu-project.org/apiref/icu4c/uidna_8h.html#ab04a0655cd1e3bcac5e8f48c18df1a57
• https://github.com/nodejs/node/blob/6c213978b7c790b7b716df75deab45c3681e5a20/test/fixtures/url-idna.js#L192-L201
• https://github.com/nodejs/Intl/issues/44

Updates

• src: support domains with empty labels in i18n
• test: synchronise WPT url test data

Checklist

• make -j4 test
• tests are included
• commit message follows commit guidelines

Affected core subsystem(s)

src, test