[master] RFR: 8302209: [Lilliput] Optimize fix-anon monitor owner path

[Roman Kennke]

When trying to exit a monitor, we need to check if the current owner is anonymous, and if so, fix it before exiting the monitor. So far, we have been doing this by calling into the slow-path and handle it in the runtime. However, it is fairly easy to do in the fast-path and avoid calling into the runtime altogether.

Testing:
 - [x] tier1 (x86_64, aarch64)
 - [ ] tier2 (x86_64, aarch64)
 - [ ] jcstress -t sync -m quick

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Commit messages:
 - 8302209: [Lilliput] Optimize fix-anon monitor owner path

Changes: https://git.openjdk.org/lilliput/pull/74/files
 Webrev: https://webrevs.openjdk.org/?repo=lilliput&pr=74&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8302209
  Stats: 60 lines in 5 files changed: 55 ins; 1 del; 4 mod
  Patch: https://git.openjdk.org/lilliput/pull/74.diff
  Fetch: git fetch https://git.openjdk.org/lilliput pull/74/head:pull/74

PR: https://git.openjdk.org/lilliput/pull/74