<i18n dev> RFR: JDK-8314611: Provide more explicative error message parsing Currencies [v4]

[Justin Lu]

> Please review this PR which updates some exceptions in j.util.Currency to have an explicit error message (as opposed to nothing).
> 
> The exceptions are thrown when the ISO 4217/3166 currency/country codes are in an invalid form, or do not exist.

Justin Lu has updated the pull request incrementally with one additional commit since the last revision:

  Change wording in test as well

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Changes:
  - all: https://git.openjdk.org/jdk/pull/15458/files
  - new: https://git.openjdk.org/jdk/pull/15458/files/d134adf8..96efc13a

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=15458&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=15458&range=02-03

  Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/15458.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15458/head:pull/15458

PR: https://git.openjdk.org/jdk/pull/15458