RFR: 8304674: AttachCurrentThread 's argument is JavaVMAttachArgs

[tison]

Try to add clear type annotations.

Please let me know how this patch can be properly reviewed >_<

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Commit messages:
 - chore: AttachCurrentThread 's argument is JavaVMAttachArgs

Changes: https://git.openjdk.org/jdk/pull/21658/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21658&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8304674
  Stats: 4 lines in 1 file changed: 0 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/21658.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21658/head:pull/21658

PR: https://git.openjdk.org/jdk/pull/21658