[lworld] RFR: 8209554: [lworld] ClassCastException thrown for JCK test instead of expected IllegalArgumentException

[Roger Riggs]

This reverts the workaround added in JDK-8207815.
The implementations of Array::set and Array::get match mainline after this.

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Commit messages:
 - 8209555: [lworld] ClassCastException thrown for JCK test instead of expected IllegalArgumentException

Changes: https://git.openjdk.org/valhalla/pull/1753/files
  Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=1753&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8209554
  Stats: 37 lines in 3 files changed: 7 ins; 20 del; 10 mod
  Patch: https://git.openjdk.org/valhalla/pull/1753.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1753/head:pull/1753

PR: https://git.openjdk.org/valhalla/pull/1753