RFR: 8366678: Use JUnit in test/langtools/tools/javac [v2]

[Christian Stein]

> Please review this change to use JUnit in tests of `test/langtools/tools/javac`.
> 
> ### Assess Status Quo
> A local `make test TEST=test/langtools/tools/javac` run before the conversion yields:
> 
> Test results: passed: 3,938; excluded: 4; did not match keywords: 2; did not meet platform requirements: 2
> Framework-based tests: 3043 = 2762 TestNG + 281 JUnit
> 
> 
> ### Perform Automatic Conversion
> - [junit-convert](
> https://github.com/lahodaj/netbeans/tree/openjdk-testng-junit-fixes-and-hacks/java/java.openjdk.project/junit-convert)
> 
> ### Perform Manual Adjustments
> 
> Some of the following adjustments will be integrated into the `junit-convert` tool.
> 
> #### Make argument source factory method `static`
> 
> Method 'public java.lang.Object[][] org.openjdk.tests.javac.FDTest.caseGenerator()'
>   must be static: local factory methods must be static
>   unless the PER_CLASS @testinstance lifecycle mode is used;
>   external factory methods must always be static.
> 
> 
> #### Make `@AfterAll`-annotated method `static`
> 
> [ERROR] @afterall method 'public void org.openjdk.tests.vm.FDSeparateCompilationTest.cleanupCompilerCache()'
>   must be static unless the test class
>   is annotated with `@TestInstance(Lifecycle.PER_CLASS)`.
> 
> 
> #### Remove `static` modifier from `@Test`-annotated methods
> This configuration error should have been detected by JUnit Jupiter and reported via the Discovery
> Issues API: https://docs.junit.org/current/user-guide/#running-tests-discovery-issues
> 
> #### Rename test property to `JUnit.dirs`
> 
> package org.junit.jupiter.api does not exist
> 
> 
> #### Add custom test instance factory
> 
> Class [FDTests] must declare a single constructor
> Class [MethodReferenceTestKinds] must declare a single constructor
> 
> 
> ### Results
> Re-run tests via `make test TEST=test/langtools/tools/javac` after the conversion; yielding:
> 
> Test results: passed: 3,939; excluded: 4; did not match keywords: 2; did not meet platform requirements: 2
> Framework-based tests: 3043 = 0 TestNG + 3043 JUnit

Christian Stein has updated the pull request incrementally with one additional commit since the last revision:

  Update copyright year

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/27046/files
  - new: https://git.openjdk.org/jdk/pull/27046/files/5c3baed1..4fa84ef8

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=27046&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=27046&range=00-01

  Stats: 37 lines in 37 files changed: 0 ins; 0 del; 37 mod
  Patch: https://git.openjdk.org/jdk/pull/27046.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27046/head:pull/27046

PR: https://git.openjdk.org/jdk/pull/27046