[jdk11u-dev] RFR: 8301570: Test runtime/jni/nativeStack/ needs to detach the native thread

[Amos]

- Backport of [JDK-8301570](https://bugs.openjdk.org/browse/JDK-8301570)
- Test succeeded in local dev box

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Commit messages:
 - Backport d269ebbad2286b57802a075091b0cc32110dfcc7

Changes: https://git.openjdk.org/jdk11u-dev/pull/2183/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2183&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8301570
  Stats: 8 lines in 1 file changed: 7 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2183.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2183/head:pull/2183

PR: https://git.openjdk.org/jdk11u-dev/pull/2183