RFR: 8310843: Reimplement ByteArray and ByteArrayLittleEndian with Unsafe [v2]

[Glavo]

> Things have changed since https://github.com/openjdk/jdk/pull/14636 was closed, so let me reopen it.
> 
> https://github.com/openjdk/jdk/pull/15386 confirmed that `VarHandle` in BALE caused a startup regression. In order to not have any more revert patches, it makes sense to optimize BALE.
> 
> The optimization of https://github.com/openjdk/jdk/pull/16245 allows the traditional expression to have good performance, but BA and BALE save us from having to copy these lengthy expressions everywhere. So it makes sense to keep them.
> 
> Now here's the question, should I rewrite this PR without `Unsafe`? I'll do some research (e.g. does `Unsafe` have better performance during warmup?), but I'd also like to take some advice.

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

  update copyright

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Changes:
  - all: https://git.openjdk.org/jdk/pull/19616/files
  - new: https://git.openjdk.org/jdk/pull/19616/files/b3920c86..332bb270

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=19616&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=19616&range=00-01

  Stats: 3 lines in 3 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/19616.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19616/head:pull/19616

PR: https://git.openjdk.org/jdk/pull/19616