RFR: Merge jdk19

[Jesper Wilhelmsson]

Forwardport JDK 19 -> JDK 20

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Commit messages:
 - Merge
 - 8288112: C2: Error: ShouldNotReachHere() in Type::typerr()
 - 8290209: jcup.md missing additional text
 - 8290207: Missing notice in dom.md

The webrevs contain the adjustments done while merging with regards to each parent branch:
 - master: https://webrevs.openjdk.org/?repo=jdk&pr=9493&range=00.0
 - jdk19: https://webrevs.openjdk.org/?repo=jdk&pr=9493&range=00.1

Changes: https://git.openjdk.org/jdk/pull/9493/files
  Stats: 242 lines in 11 files changed: 232 ins; 2 del; 8 mod
  Patch: https://git.openjdk.org/jdk/pull/9493.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9493/head:pull/9493

PR: https://git.openjdk.org/jdk/pull/9493