[jdk17u-dev] RFR: 8313816: Accessing jmethodID might lead to spurious crashes

[Jaroslav Bachorik]

Reviewed-by: coleenp

A minor update required for the backport - the original changeset is using `nullptr` while the JDK 17 version is using `NULL`

Attaching the conflicting file for posterity.

[instanceKlass.cpp](https://github.com/openjdk/jdk17u-dev/files/13504341/InstanceKlass_conflict.txt)

Additionally,  I had to bring in a few test support classes as well - https://github.com/openjdk/jdk17u-dev/pull/2001/commits/d59ac82d5b4d3cace38e38cb7747642aaee98ba4

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Commit messages:
 - Add test support files
 - 8313816: Accessing jmethodID might lead to spurious crashes

Changes: https://git.openjdk.org/jdk17u-dev/pull/2001/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2001&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8313816
  Stats: 1226 lines in 11 files changed: 1224 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2001.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2001/head:pull/2001

PR: https://git.openjdk.org/jdk17u-dev/pull/2001