[jdk18u] RFR: 8278065: Refactor subclassAudits to use ClassValue [v2]

[Roman Kennke]

> This backports the fix for JDK-8278065, which fixes a number of small issues with the preceding change for JDK-8277072.
> The original change has baked for several weeks in jdk19 and applies cleanly.
> 
> Testing:
>  - [x] tier1
>  - [x] tier2
>  - [x] tier3

Roman Kennke 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.

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Changes:
  - all: https://git.openjdk.java.net/jdk18u/pull/50/files
  - new: https://git.openjdk.java.net/jdk18u/pull/50/files/482d41e7..482d41e7

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk18u&pr=50&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk18u&pr=50&range=00-01

  Stats: 0 lines in 0 files changed: 0 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk18u/pull/50.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk18u pull/50/head:pull/50

PR: https://git.openjdk.java.net/jdk18u/pull/50