[jdk11u-dev] RFR: 8309104: [JVMCI] compiler/unsafe/UnsafeGetStableArrayElement test asserts wrong values with Graal

[Amos Shi]

Backport of [JDK-8309104](https://bugs.openjdk.org/browse/JDK-8309104)
- `test/hotspot/jtreg/compiler/unsafe/UnsafeGetStableArrayElement.java`
  - `Copyright year` line manually merged (`unclean`), all other code changes are `clean`

Testing
- Local: `Passed`
- Pipeline: 
- Testing Machine:

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Commit messages:
 - Backport 11fb5b2209124bbf1100657e340ba5aebc3820d7

Changes: https://git.openjdk.org/jdk11u-dev/pull/2491/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2491&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8309104
  Stats: 11 lines in 1 file changed: 0 ins; 0 del; 11 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2491.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2491/head:pull/2491

PR: https://git.openjdk.org/jdk11u-dev/pull/2491