[lworld] Integrated: 8261782: [lworld] Add support for PrimitiveObject interface

[Srikanth Adayapalam]

- Compiler support for PrimitiveObject top type

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Commit messages:
 - 8261782: [lworld] Add support for PrimitiveObject interface

Changes: https://git.openjdk.java.net/valhalla/pull/344/files
 Webrev: https://webrevs.openjdk.java.net/?repo=valhalla&pr=344&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8261782
  Stats: 162 lines in 8 files changed: 150 ins; 1 del; 11 mod
  Patch: https://git.openjdk.java.net/valhalla/pull/344.diff
  Fetch: git fetch https://git.openjdk.java.net/valhalla pull/344/head:pull/344

PR: https://git.openjdk.java.net/valhalla/pull/344