RFR: JDK-8323330: undo JDK-8276809 and bring back JNI warning

[Matthias Baesken]

There have been concerns raised about [JDK-8276809](https://bugs.openjdk.org/browse/JDK-8276809) , so bring back the old behavior.

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Commit messages:
 - JDK-8323330

Changes: https://git.openjdk.org/jdk/pull/17341/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17341&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8323330
  Stats: 8 lines in 1 file changed: 0 ins; 6 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/17341.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17341/head:pull/17341

PR: https://git.openjdk.org/jdk/pull/17341