[omworld-jdk] RFR: 8326761: Lilliput: OMWorld: Fix invalid markWord transition

[Axel Boldt-Christmas]

`PlaceholderSynchronizer::inflate_and_enter` currently performs an invalid transition of the markWord away from monitor. This may lead to an ABA issue.

This got opportunistically added at some point to avoid spinning on the deflation thread progress. The issue of guaranteed progress is not something that has been observed as an issue. If guaranteed progress turns out to be required there are solutions which do not have ABA issues, but it requires extra state in the already heavily contested markWord.

The yielding and spinning will be evaluated in a separate issue.

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Commit messages:
 - Locking thread cannot help transition the markword

Changes: https://git.openjdk.org/lilliput/pull/138/files
 Webrev: https://webrevs.openjdk.org/?repo=lilliput&pr=138&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8326761
  Stats: 10 lines in 1 file changed: 0 ins; 8 del; 2 mod
  Patch: https://git.openjdk.org/lilliput/pull/138.diff
  Fetch: git fetch https://git.openjdk.org/lilliput.git pull/138/head:pull/138

PR: https://git.openjdk.org/lilliput/pull/138