RFR: JDK-8291509 Minor cleanup could be done in sun.security [v2]

[Mark Powers]

> https://bugs.openjdk.org/browse/JDK-8291509

Mark Powers has updated the pull request incrementally with one additional commit since the last revision:

  remove requireNonNull

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/9972/files
  - new: https://git.openjdk.org/jdk/pull/9972/files/9ca27fad..c23d248b

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=9972&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=9972&range=00-01

  Stats: 523 lines in 57 files changed: 5 ins; 189 del; 329 mod
  Patch: https://git.openjdk.org/jdk/pull/9972.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9972/head:pull/9972

PR: https://git.openjdk.org/jdk/pull/9972