[code-reflection] RFR: Committing a Concatenation transformation to StringBuilder

[Ian Graves]

A transformation that converts String Concatenation to StringBuilder for uses in lowering to Bytecode.

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Commit messages:
 - Committing a Concatenation transformation to StringBuilder

Changes: https://git.openjdk.org/babylon/pull/135/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=135&range=00
  Stats: 368 lines in 3 files changed: 368 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/babylon/pull/135.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/135/head:pull/135

PR: https://git.openjdk.org/babylon/pull/135