[jdk21u-dev] RFR: 8337876: [IR Framework] Add support for IR tests with @Stable

[Aleksey Shipilev]

Improves IR test framework in preparation for `@Stable` fixes.

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Commit messages:
 - Backport 0e7c1c1afeaba1c125b70cabe7b1b7a3193ee5c3
 - Backport c01f53ac2dab1d4d2cd1e4d45a67f9373d4a9c7e

Changes: https://git.openjdk.org/jdk21u-dev/pull/1043/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk21u-dev&pr=1043&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8337876
  Stats: 103 lines in 5 files changed: 96 ins; 0 del; 7 mod
  Patch: https://git.openjdk.org/jdk21u-dev/pull/1043.diff
  Fetch: git fetch https://git.openjdk.org/jdk21u-dev.git pull/1043/head:pull/1043

PR: https://git.openjdk.org/jdk21u-dev/pull/1043