[code-reflection] Integrated: Hat view more experiments

[Gary Frost]

More experiments representing vectors as ifaces and having javaside collections in pools/lists

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Commit messages:
 - add copyright
 - Simplify pool access
 - Simplify pool access
 - cleanup

Changes: https://git.openjdk.org/babylon/pull/681/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=681&range=00
  Stats: 991 lines in 23 files changed: 363 ins; 432 del; 196 mod
  Patch: https://git.openjdk.org/babylon/pull/681.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/681/head:pull/681

PR: https://git.openjdk.org/babylon/pull/681