[jdk21u-dev] RFR: 8319376: ParallelGC: Forwarded objects found during heap inspection

[Liang Mao]

Clean backport of fixing the potential self forwarding object in heap inspection of Parallel GC

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Commit messages:
 - Backport 59e9981ec21258b8aa5f93cb1fb9b0ccf9f846af

Changes: https://git.openjdk.org/jdk21u-dev/pull/544/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=544&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8319376
  Stats: 12 lines in 1 file changed: 11 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/544.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/544/head:pull/544

PR: https://git.openjdk.org/jdk21u-dev/pull/544