RFR: 8375571: Compiler crash when using record pattern matching with a generic type parameter shadowing a record class

[Jan Lahoda]

Consider code like:

    <T> void typeVarTest(T p) {
        if (p instanceof T(int i) && i == 0); //T is a type variable
    }


The `T` in the deconstruction pattern will be resolve to `TypeVariableSymbol`, which has kind `TYP`, but is not `ClassSymbol`, so the cast will fail. Using `instanceof ClassSymbol` would work better, which is what this PR is doing.

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Commit messages:
 - Updating copyright year.
 - 8375571: Compiler crash when using record pattern matching with a generic type parameter shadowing a record class

Changes: https://git.openjdk.org/jdk/pull/29407/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29407&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8375571
  Stats: 31 lines in 3 files changed: 7 ins; 1 del; 23 mod
  Patch: https://git.openjdk.org/jdk/pull/29407.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29407/head:pull/29407

PR: https://git.openjdk.org/jdk/pull/29407