[lworld] RFR: 8373202: [lworld] ObjectReference.equals should follow == semantics for value objects

[Alex Menkov]

Updated implementation of ObjectReference.equals and ObjectReference.hashCode to comply the spec for value objects.
Added the test for value object ctor debugging, the test verifies the behaviour is expected.
There is an issue with instance filter, it till be fixed separately (it's not yet clear how it would be better to fix it)

testing: tier1..4, hs-tier5-svc

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Commit messages:
 - ObjectReferenceImp.hashCode
 - Merge branch 'ctor_debug' of github.com:alexmenkov/valhalla into ctor_debug
 - tabs
 - fix
 - IsSameObject only for value objects
 - tabs
 - fix
 - Merge branch 'openjdk:lworld' into lworld
 - Merge branch 'openjdk:lworld' into lworld
 - Merge branch 'openjdk:lworld' into lworld
 - ... and 3 more: https://git.openjdk.org/valhalla/compare/13abe7d1...f82f5be4

Changes: https://git.openjdk.org/valhalla/pull/1834/files
  Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=1834&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8373202
  Stats: 536 lines in 6 files changed: 530 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/valhalla/pull/1834.diff
  Fetch: git fetch https://git.openjdk.org/valhalla.git pull/1834/head:pull/1834

PR: https://git.openjdk.org/valhalla/pull/1834