RFR: 8338007: [JVMCI] ResolvedJavaMethod.reprofile can crash ciMethodData

[Tom Rodriguez]

Graal unit testing uses ResolvedJavaMethod.reprofile to reset profiles between test but the current code rewrites the layout in a non-atomic way which can break other readers.  Instead perform the reinitialization at a safepoint which should protect all readers from seeing any transient initialization states.

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Commit messages:
 - 8338007: [JVMCI] ResolvedJavaMethod.reprofile can crash ciMethodData

Changes: https://git.openjdk.org/jdk/pull/21746/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21746&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8338007
  Stats: 41 lines in 4 files changed: 35 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/21746.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21746/head:pull/21746

PR: https://git.openjdk.org/jdk/pull/21746