[lworld] RFR: 8297207: [lworld] refactor primitive classes tests

[Vicente Romero]

refactoring primitive classes tests, consolidating compilation tests etc

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Commit messages:
 - additional changes
 - 8297207: [lworld] refactor primitive classes tests

Changes: https://git.openjdk.org/valhalla/pull/811/files
 Webrev: https://webrevs.openjdk.org/?repo=valhalla&pr=811&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8297207
  Stats: 555 lines in 8 files changed: 325 ins; 230 del; 0 mod
  Patch: https://git.openjdk.org/valhalla/pull/811.diff
  Fetch: git fetch https://git.openjdk.org/valhalla pull/811/head:pull/811

PR: https://git.openjdk.org/valhalla/pull/811