[jdk17u] RFR: 8273234: extended 'for' with expression of type tvar causes the compiler to crash

[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, new test fails without the patch, passes with it.

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Commit messages:
 - Backport 8c379092747301de70db1ef8e441cbe09fd742e7

Changes: https://git.openjdk.java.net/jdk17u/pull/175/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk17u&pr=175&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8273234
  Stats: 50 lines in 2 files changed: 49 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk17u/pull/175.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17u pull/175/head:pull/175

PR: https://git.openjdk.java.net/jdk17u/pull/175