RFR: Merge jdk18 [v2]

[Jesper Wilhelmsson]

> Forwardport JDK 18 -> JDK 19

Jesper Wilhelmsson has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains 53 additional commits since the last revision:

 - Merge
 - 8278020: ~13% variation in Renaissance-Scrabble
   
   Reviewed-by: dholmes, stuefe, kvn
 - 8274898: Cleanup usages of StringBuffer in jdk tools modules
   
   Reviewed-by: sspitsyn, lmesnik
 - 8269838: BasicTypeDataBase.findDynamicTypeForAddress(addr, basetype) can be simplified
   
   Reviewed-by: kevinw, sspitsyn
 - 8278186: org.jcp.xml.dsig.internal.dom.Utils.parseIdFromSameDocumentURI throws StringIndexOutOfBoundsException when calling substring method
   
   Reviewed-by: mullan
 - 8278241: Implement JVM SpinPause on linux-aarch64
   
   Reviewed-by: aph, phh
 - 8278842: Parallel: Remove unused VerifyObjectStartArrayClosure::_old_gen
   
   Reviewed-by: tschatzl
 - 8278548: G1: Remove unnecessary check in forward_to_block_containing_addr
   
   Reviewed-by: tschatzl, mli, sjohanss
 - 8202579: Revisit VM_Version and VM_Version_ext for overlap and consolidation
   
   Reviewed-by: dholmes, hseigel
 - 8278351: Add function to retrieve worker_id from any context
   
   Reviewed-by: eosterlund, kbarrett, ayang
 - ... and 43 more: https://git.openjdk.java.net/jdk/compare/6d63c6dd...fa3d80e6

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/6856/files
  - new: https://git.openjdk.java.net/jdk/pull/6856/files/fa3d80e6..fa3d80e6

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=6856&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=6856&range=00-01

  Stats: 0 lines in 0 files changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6856.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6856/head:pull/6856

PR: https://git.openjdk.java.net/jdk/pull/6856