RFR: 8335836: serviceability/jvmti/StartPhase/AllowedFunctions/AllowedFunctions.java fails with unexpected exit code: 112

[Serguei Spitsyn]

The test has been fixed to:
 - add a guard against JVMTI_ERROR_WRONG_PHASE
 - replace `exit(err)` with `abort()` in the `check_jvmti_error()`
 
The JVMTI `VMDeath` event is enabled and a `RawMonitor` is introduced to prevent JVMTI_ERROR_WRONG_PHASE in the `ClassPrepare` events.

Testing:
 - run the test AllowedFunctions.java locally
 - TBD: submit a mach5 run for fixed test

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Commit messages:
 - 8335836: serviceability/jvmti/StartPhase/AllowedFunctions/AllowedFunctions.java fails with unexpected exit code: 112

Changes: https://git.openjdk.org/jdk/pull/20397/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20397&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8335836
  Stats: 32 lines in 1 file changed: 29 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/20397.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20397/head:pull/20397

PR: https://git.openjdk.org/jdk/pull/20397