[code-reflection] RFR: Determine if lambda operation originates from a method reference

[Paul Sandoz]

Add a method to determines if a lambda operation could have originated from a method reference declared in Java source code.

Consider later generalizing to a lambda operation that may have originated from a lambda expression that only invokes another method, which may include the capturing of some or all method arguments.

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

Commit messages:
 - Determine if lambda operation originates from a method reference

Changes: https://git.openjdk.org/babylon/pull/60/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=60&range=00
  Stats: 276 lines in 2 files changed: 219 ins; 2 del; 55 mod
  Patch: https://git.openjdk.org/babylon/pull/60.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/60/head:pull/60

PR: https://git.openjdk.org/babylon/pull/60