RFR: 8370839: Tests to verify peculiar Proxy dispatching behaviors [v5]

[Chen Liang]

> java.lang.reflect.Proxy has some surprising behaviors associated with protected methods in Object, covariant/contravariant overrides in interfaces, and package-private types in method signatures. Such behaviors should have tests, so that they are not accidentally perturbed in Proxy updates.

Chen Liang has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains nine additional commits since the last revision:

 - Better comments
 - Merge branch 'master' of https://github.com/openjdk/jdk into test/proxy-dispatches
 - Update test/jdk/java/lang/reflect/Proxy/BridgeMethodsTest.java
 - Consolidate duplicate tests
 - Merge branch 'master' of https://github.com/openjdk/jdk into test/proxy-dispatches
 - Merge branch 'master' of https://github.com/openjdk/jdk into test/proxy-dispatches
 - Merge branch 'master' of https://github.com/openjdk/jdk into test/proxy-dispatches
 - Tweaks
 - 8370839: Tests to verify peculiar Proxy dispatching behaviors

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/28023/files
  - new: https://git.openjdk.org/jdk/pull/28023/files/e8ed5fab..5cafdf2f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=28023&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=28023&range=03-04

  Stats: 160628 lines in 819 files changed: 110305 ins; 22545 del; 27778 mod
  Patch: https://git.openjdk.org/jdk/pull/28023.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28023/head:pull/28023

PR: https://git.openjdk.org/jdk/pull/28023