[code-reflection] RFR: Remove the code model transformation: addVarsWhenNecessary.

[Mourad Abbay]

We remove the code model transformation: `addVarsWhenNecessary`.

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Commit messages:
 - Remove the code model transformation: addVarsWhenNecessary.

Changes: https://git.openjdk.org/babylon/pull/387/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=387&range=00
  Stats: 102 lines in 1 file changed: 34 ins; 59 del; 9 mod
  Patch: https://git.openjdk.org/babylon/pull/387.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/387/head:pull/387

PR: https://git.openjdk.org/babylon/pull/387