[code-reflection] RFR: Unreflect tests [v4]

[Adam Sotona]

> This PR implement `Unreflect` test tool and re-runs tests in the unreflected form.
> 
> `TestSwitchExpressionOp` and `TestSwitchStatementOp` yet to be temporary excluded as failing  (see [JDK-8373573](https://bugs.openjdk.org/browse/JDK-8373573)).

Adam Sotona has updated the pull request incrementally with three additional commits since the last revision:

 - unreflect lambdas
   
 - test tags cleanup
   
 - nit fixes

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

Changes:
  - all: https://git.openjdk.org/babylon/pull/762/files
  - new: https://git.openjdk.org/babylon/pull/762/files/ff2ff45e..0ed2a375

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=babylon&pr=762&range=03
 - incr: https://webrevs.openjdk.org/?repo=babylon&pr=762&range=02-03

  Stats: 112 lines in 5 files changed: 99 ins; 5 del; 8 mod
  Patch: https://git.openjdk.org/babylon/pull/762.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/762/head:pull/762

PR: https://git.openjdk.org/babylon/pull/762