RFR: 8294693: Add Collections.shuffle overload that accepts RandomGenerator interface [v6]

[Tagir F. Valeev]

> Java 17 added RandomGenerator interface. However, existing method Collections.shuffle accepts old java.util.Random class. While since Java 19, it's possible to use Random.from(RandomGenerator) wrapper, it would be more convenient to provide direct overload shuffle(List<?> list, RandomGenerator rnd).

Tagir F. Valeev has updated the pull request incrementally with two additional commits since the last revision:

 - Whitespaces fixed
 - @implSpec added to shuffle(List)

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Changes:
  - all: https://git.openjdk.org/jdk/pull/10520/files
  - new: https://git.openjdk.org/jdk/pull/10520/files/a465bd79..37a8c9f0

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=10520&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=10520&range=04-05

  Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/10520.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10520/head:pull/10520

PR: https://git.openjdk.org/jdk/pull/10520