[jdk17u] RFR: 8274347: Passing a *nested* switch expression as a parameter causes an NPE during compile

[Ekaterina Vergizova]

I'd like to backport this fix to 17u. It fixes regression in javac introduced in jdk17.
The patch applies cleanly.
Tested with langtools tests, updated tests fail without the patch, pass with it.

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Commit messages:
 - Backport b870468bdc99938fbb19a41b0ede0a3e3769ace2

Changes: https://git.openjdk.java.net/jdk17u/pull/196/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u&pr=196&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8274347
  Stats: 88 lines in 3 files changed: 85 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk17u/pull/196.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u pull/196/head:pull/196

PR: https://git.openjdk.java.net/jdk17u/pull/196