Integrated: Adding type system regression tests

[Vicente Romero]

Adding more type system regression tests for universal type variables. Adding overload resolution for primitive classes.

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Commit messages:
 - inference related tests
 - adding type system regression tests

Changes: https://git.openjdk.java.net/valhalla/pull/628/files
 Webrev: https://webrevs.openjdk.java.net/?repo=valhalla&pr=628&range=00
  Stats: 297 lines in 10 files changed: 223 ins; 26 del; 48 mod
  Patch: https://git.openjdk.java.net/valhalla/pull/628.diff
  Fetch: git fetch https://git.openjdk.java.net/valhalla pull/628/head:pull/628

PR: https://git.openjdk.java.net/valhalla/pull/628