This is a reland of c9c3ec4c


Original change's description:
> [intl] Clean up intl_segmenter flag
>
> Intl.Segmenter shipped in m87 and launched.
>
> Bug: v8:11225
> Change-Id: I4213e261e1aea717c1281f19785a8c29ff1bbd8b
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2570461
> Commit-Queue: Frank Tang <ftang@chromium.org>
> Reviewed-by: Shu-yu Guo <syg@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#71653}

Bug: v8:11225, v8:11240
Change-Id: Ibded9038671862d90206d328f8a12db51c40e63c
Cq-Include-Trybots: luci.v8.try:v8_linux64_gc_stress_custom_snapshot_dbg_ng,v8_linux_arm64_gc_stress_dbg_ng,v8_linux_gc_stress_dbg_ng,v8_mac64_gc_stress_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2579043
Commit-Queue: Frank Tang <ftang@chromium.org>
Reviewed-by: Shu-yu Guo <syg@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71691}