When a type uses a type variable without a declaration, no exception is thrown. This change triggers a `TypeNotFoundException` to be thrown.
------------- Commit messages: - JDK-8337302: Throw exception upon search for type variable without representation. Changes: https://git.openjdk.org/jdk/pull/20535/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20535&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8337302 Stats: 84 lines in 3 files changed: 74 ins; 0 del; 10 mod Patch: https://git.openjdk.org/jdk/pull/20535.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/20535/head:pull/20535 PR: https://git.openjdk.org/jdk/pull/20535
