[code-reflection] RFR: Correct bytecode gen for lambda capture

[Paul Sandoz]

The byte code generator was incorrectly establishing the block mapping when generating models for quotable lambdas.

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Commit messages:
 - Correct bytecode gen for lambda capture

Changes: https://git.openjdk.org/babylon/pull/185/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=185&range=00
  Stats: 98 lines in 2 files changed: 95 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/babylon/pull/185.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/185/head:pull/185

PR: https://git.openjdk.org/babylon/pull/185