<i18n dev> RFR: 8366178: Implement JEP 526: Lazy Constants (Second Preview) [v6]

[Per Minborg]

> Implement JEP 526: Lazy Constants (Second Preview)
> 
> The lazy list/map implementations are broken out from `ImmutableCollections` to a separate class.
> 
> The old benchmarks are not moved/renamed to allow comparison with previous releases.
> 
> `java.util.Optional` is updated so that its field is annotated with `@Stable`.  This is to allow `Optional` instances to be held in lazy constants and still provide constant folding.

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

  Define constant folding

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/27605/files
  - new: https://git.openjdk.org/jdk/pull/27605/files/ea14b8f9..e25eeb9b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=27605&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=27605&range=04-05

  Stats: 7 lines in 1 file changed: 1 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/27605.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27605/head:pull/27605

PR: https://git.openjdk.org/jdk/pull/27605