RFR: 8253635: Implement toString() for SSLEngineImpl [v2]

[Xue-Lei Andrew Fan]

> The SSLSocketImpl and SSLEngineImpl implementation does not override the toString() method.  The old code did.  BTW, I also made a few code clean up in the SSLSocketImpl.java.
> 
> Code clean up, trivial update, no new regression test.

Xue-Lei Andrew Fan 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 three additional commits since the last revision:

 - Merge master
 - missing a white space
 - 8253635: Implement toString() for SSLEngineImpl

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/2019/files
  - new: https://git.openjdk.java.net/jdk/pull/2019/files/78e12edf..6600ee32

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=2019&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=2019&range=00-01

  Stats: 8715 lines in 333 files changed: 5636 ins; 1731 del; 1348 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2019.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2019/head:pull/2019

PR: https://git.openjdk.java.net/jdk/pull/2019