RFR: 8304283: Modernize the switch statements in jdk.internal.foreign [v3]

[Per Minborg]

> This PR proposes changing old-type switch statements to newer forms of switch.

Per Minborg has updated the pull request incrementally with one additional commit since the last revision:

  Update after comments

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Changes:
  - all: https://git.openjdk.org/jdk/pull/13047/files
  - new: https://git.openjdk.org/jdk/pull/13047/files/e9b157e7..f20f3516

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=13047&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13047&range=01-02

  Stats: 37 lines in 2 files changed: 12 ins; 0 del; 25 mod
  Patch: https://git.openjdk.org/jdk/pull/13047.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/13047/head:pull/13047

PR: https://git.openjdk.org/jdk/pull/13047