<i18n dev> RFR: JDK-8210410: Refactor java.util.Currency:i18n shell tests to plain java tests [v2]

[Justin Lu]

> Please review this PR which converts the shell test, _java/util/currency/PropertiesTest.sh_ to a normal java test.
> 
> This test is a test runner that launches test methods from _PropertiesTest.java_. It tests both the ways to supersede the default currencies, that is, either using a custom properties file under the lib directory, or setting the path to a custom properties file via the system property.

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

  cleanup + naming

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/16787/files
  - new: https://git.openjdk.org/jdk/pull/16787/files/780c6fd1..efc6da98

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=16787&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=16787&range=00-01

  Stats: 40 lines in 1 file changed: 8 ins; 10 del; 22 mod
  Patch: https://git.openjdk.org/jdk/pull/16787.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16787/head:pull/16787

PR: https://git.openjdk.org/jdk/pull/16787