RFR: 8336491: Unnecessary boxing conversions in void-returning lambdas [v3]

[Liam Miller-Cushon]

> Please consider this possible fix for [JDK-8336491](https://bugs.openjdk.org/browse/JDK-8336491), which avoids generating an unnecessary boxing conversion for the result of void-returning expression lambdas.

Liam Miller-Cushon has updated the pull request incrementally with one additional commit since the last revision:

  Represent void lambda results as Type.noType

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Changes:
  - all: https://git.openjdk.org/jdk/pull/20222/files
  - new: https://git.openjdk.org/jdk/pull/20222/files/3f319f11..2113c06e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=20222&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20222&range=01-02

  Stats: 5 lines in 1 file changed: 4 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/20222.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20222/head:pull/20222

PR: https://git.openjdk.org/jdk/pull/20222