[code-reflection] RFR: Test Switch Expression lowering when case is constant [v3]

[Mourad Abbay]

> Test Switch Expression lowering when case is constant.

Mourad Abbay has updated the pull request incrementally with three additional commits since the last revision:

 - Write code models without location info
 - Fix a typo
 - Add compiler tests of Switch Expression.

-------------

Changes:
  - all: https://git.openjdk.org/babylon/pull/169/files
  - new: https://git.openjdk.org/babylon/pull/169/files/1457f1fe..f4c40ea9

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=babylon&pr=169&range=02
 - incr: https://webrevs.openjdk.org/?repo=babylon&pr=169&range=01-02

  Stats: 651 lines in 2 files changed: 647 ins; 1 del; 3 mod
  Patch: https://git.openjdk.org/babylon/pull/169.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/169/head:pull/169

PR: https://git.openjdk.org/babylon/pull/169