RFR: 8211400: nsk.share.gc.Memory::getArrayLength returns wrong value

[Ramkumar Sunderbabu]

Current formula is incorrect since array doesn't use reference for each element.

Tested with test groups,
vmTestbase_vm_gc_ref
vmTestbase_vm_gc_juggle
vmTestbase_vm_gc_misc

-------------

Commit messages:
 - 8211400: nsk.share.gc.Memory::getArrayLength returns wrong value

Changes: https://git.openjdk.org/jdk/pull/21247/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21247&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8211400
  Stats: 7 lines in 1 file changed: 0 ins; 3 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/21247.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21247/head:pull/21247

PR: https://git.openjdk.org/jdk/pull/21247