[lworld] RFR: 8244931: [lworld] Decommission arrayStorageProperties from runtime null free and flat array tests

[David Simms]

Moved runtime and interpreter flat & null free tests to klass layout helper

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

Commit messages:
 - 8244931: [lworld] Decommission arrayStorageProperties from runtime null free and flat array tests

Changes: https://git.openjdk.java.net/valhalla/pull/54/files
 Webrev: https://webrevs.openjdk.java.net/valhalla/54/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8244931
  Stats: 80 lines in 9 files changed: 51 ins; 4 del; 25 mod
  Patch: https://git.openjdk.java.net/valhalla/pull/54.diff
  Fetch: git fetch https://git.openjdk.java.net/valhalla pull/54/head:pull/54

PR: https://git.openjdk.java.net/valhalla/pull/54