[css-text-3] Upstream small Kana to Kana mapping to Unicode

[annevk]

I was made aware of https://www.w3.org/TR/css-text-3/#small-kana and after some research it appears this isn't backed by data in Unicode. That makes me a little nervous.

@frivoal would you be up for asking Unicode through http://unicode.org/reporting.html to see if they would be willing to take over maintenance of this mapping? That way it will also eventually make its way into ICU and similar tooling and we can be more confident it'll be consistent and correct over time.

Thanks!

[Crissov]

This sounds like a very good idea since the mapping table in Appendix G does not seem complete: all nine characters from the Unicode block Small Kana Extension U+1B130…6F are not listed.

[frivoal]

Didn't see this before now. I agree it should be done, but I suspect that should be brought to Unicode by the W3C-Unicode Liaison, which isn't me (probably @r12a).

This sounds like a very good idea since the mapping table in Appendix G does not seem complete: all nine characters from the Unicode block Small Kana Extension U+1B130…6F are not listed.

That is a part we can and should do.

[fantasai]

Leaving the issue open to track upstreaming, but we've at least updated the tables to Unicode 15.

[frivoal]

Filed by @xfq at https://unicode-org.atlassian.net/browse/CLDR-17044