RFR: 8308108: Support Unicode extension for collation settings [v3]

[Roger Riggs]

On Thu, 18 May 2023 19:44:01 GMT, Naoto Sato <naoto at openjdk.org> wrote:

>> This change intends to interpret the BCP47 U extension wrt collation settings in the given `Locale`, then applies them to the created instances in the 1-arg factory method in `Collator`. A corresponding CSR has also been drafted.
>
> Naoto Sato has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Added a table for possible BCP47 values and their mappings

Looks good

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Marked as reviewed by rriggs (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/14040#pullrequestreview-1433363782