icu-case-mapping should not be specified; it's on by default and will go away in v8.

[jungshik]

Version: output of node -v
Platform: All platform
Subsystem:

• Version:
• Platform:
• Subsystem:

node.js apparently specifies 'icu-case-mapping' for v8, but it's not necessary because it's ON by default for a while.

Moreover, it's going away (see https://chromium-review.googlesource.com/c/534541/ ).

@srl295

[bnoordhuis]

#13698