[lworld] RFR: 8271924: [lworld] Crashes in ZBarrierSetRuntime::load_barrier_on_oop_array

[Tobias Hartmann]

- Cherry picking the fix for [JDK-8271925](https://bugs.openjdk.java.net/browse/JDK-8271925) (mainline issue) to give it some more testing in Valhalla and to get the CI clean (it currently only reproduces in Valhalla).
- Moved TestNativeClone.java to the ZGC problem list because no other GCs are affected. I'll remove it from the problem list once [JDK-8271925](https://bugs.openjdk.java.net/browse/JDK-8271925) got fixed in mainline.
- Fixed the missing merge of [JDK-8269828](https://bugs.openjdk.java.net/browse/JDK-8269828).
- Fixed an intermittent crash/assert in `ciKlass::is_subtype_of` because `this` is not loaded.

Best regards,
Tobias

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Commit messages:
 - Fixed merge of JDK-8269828
 - 8271924: [lworld] Crashes in ZBarrierSetRuntime::load_barrier_on_oop_array

Changes: https://git.openjdk.java.net/valhalla/pull/523/files
 Webrev: https://webrevs.openjdk.java.net/?repo=valhalla&pr=523&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8271924
  Stats: 24 lines in 6 files changed: 8 ins; 1 del; 15 mod
  Patch: https://git.openjdk.java.net/valhalla/pull/523.diff
  Fetch: git fetch https://git.openjdk.java.net/valhalla pull/523/head:pull/523

PR: https://git.openjdk.java.net/valhalla/pull/523