RFR: 8163498: Many long-running security libs tests [v4]

[Fernando Guallini]

> The following tests have been split based on lower/higher key sizes in order to reduce individual execution time and run in parallel with jtreg
> sun/security/provider/DSA/SupportedDSAParamGen.java
> sun/security/provider/NSASuiteB/TestDSAGenParameterSpec.java
> com/sun/crypto/provider/KeyAgreement/SupportedDHParamGens.java
> 
> sun/security/rsa/SignatureTest.java is now using a fake generator since its objective is to test signature not key generation itself. In addition, it was generating and verifying the same key twice, with same modulus and exponent. That redundancy is removed. This speeds up the execution from ~54s to ~25s on average

Fernando Guallini has updated the pull request incrementally with one additional commit since the last revision:

  add short description regarding test split.

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/2381/files
  - new: https://git.openjdk.java.net/jdk/pull/2381/files/56ff061e..e408a627

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=2381&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=2381&range=02-03

  Stats: 41 lines in 7 files changed: 37 ins; 1 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2381.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2381/head:pull/2381

PR: https://git.openjdk.java.net/jdk/pull/2381