[code-reflection] RFR: Lower SwitchExpressionOp [v2]

[Mourad Abbay]

> Lowering of SwitchExpressionOp

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

 - Fix a typo in the doc
 - More tests
 - rename variable to avoid confusion
 - Handle switch fallthrough and make JavaYieldOp Lowerable

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Changes:
  - all: https://git.openjdk.org/babylon/pull/45/files
  - new: https://git.openjdk.org/babylon/pull/45/files/37bc19d8..1d7fcffa

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=babylon&pr=45&range=01
 - incr: https://webrevs.openjdk.org/?repo=babylon&pr=45&range=00-01

  Stats: 93 lines in 2 files changed: 77 ins; 0 del; 16 mod
  Patch: https://git.openjdk.org/babylon/pull/45.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/45/head:pull/45

PR: https://git.openjdk.org/babylon/pull/45