[lworld] RFR: 8352613: [lworld] New Unsafe API for special array creation needed by VarHandle

[Frederic Parain]

New Unsafe API to help the implementation of VarHandle's CAS operations on flat values.

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Commit messages:
 - New Unsafe API for special array creation

Changes: https://git.openjdk.org/valhalla/pull/1404/files
  Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=1404&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8352613
  Stats: 130 lines in 3 files changed: 130 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/valhalla/pull/1404.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1404/head:pull/1404

PR: https://git.openjdk.org/valhalla/pull/1404