[lworld] RFR: 8279901: [lworld] Javac should verify/ensure that a Functional interface implements neither IdentityObject nor ValueObject

[Srikanth Adayapalam]

Disqualify interfaces that extend either of the top interface types from being lambda target types.

-------------

Commit messages:
 - 8279901:  Javac should verify/ensure that a Functional interface implements neither IdentityObject nor ValueObject

Changes: https://git.openjdk.java.net/valhalla/pull/601/files
 Webrev: https://webrevs.openjdk.java.net/?repo=valhalla&pr=601&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8279901
  Stats: 89 lines in 5 files changed: 85 ins; 1 del; 3 mod
  Patch: https://git.openjdk.java.net/valhalla/pull/601.diff
  Fetch: git fetch https://git.openjdk.java.net/valhalla pull/601/head:pull/601

PR: https://git.openjdk.java.net/valhalla/pull/601