[code-reflection] RFR: Initializers prototype implementation

[Adam Sotona]

Initializers prototype implementation

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Commit messages:
 - Initializers implementation

Changes: https://git.openjdk.org/babylon/pull/339/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=339&range=00
  Stats: 141 lines in 6 files changed: 110 ins; 10 del; 21 mod
  Patch: https://git.openjdk.org/babylon/pull/339.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/339/head:pull/339

PR: https://git.openjdk.org/babylon/pull/339