RFR: 8360679: Shenandoah: AOT saved adapter calls into broken GC barrier stub

[Aleksey Shipilev]

See the bug for more analysis. This is AOT-, AArch64-, Shenandoah-specific problem. The fix is simple, the failure is catastrophic, and it is very reproducible. So it makes the issue P2, and would like to get it into JDK 25 under RDP 2 rules.

Additional testing:
 - [x] Linux AArch64 server fastdebug, mainline, `runtime/cds` with `-XX:+UseShenandoahGC` (now passes)
 - [x] Linux AArch64 server fastdebug, mainline, `hotspot_gc_shenandoah` (still passes)
 - [x] Linux AArch64 server fastdebug, JDK 25, `runtime/cds` with `-XX:+UseShenandoahGC` (now passes)
 - [x] Linux AArch64 server fastdebug, JDK 25, `hotspot_gc_shenandoah` (still passes)

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Commit messages:
 - Better comment
 - Actually the most paranoid variant is not trusting AOT cache status
 - More paranoid fix for JDK 25
 - Fix

Changes: https://git.openjdk.org/jdk/pull/26449/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=26449&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8360679
  Stats: 2 lines in 1 file changed: 1 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/26449.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/26449/head:pull/26449

PR: https://git.openjdk.org/jdk/pull/26449