RFR: 8326381: com.sun.net.httpserver.HttpsParameters and SSLStreams incorrectly handle needClientAuth and wantClientAuth

[Jaikiran Pai]

Can I please get a review of this change which proposes to fix https://bugs.openjdk.org/browse/JDK-8326381?

As noted in the JBS issue, the implementation in `setNeedClientAuth()` and `setWantClientAuth()` of `com.sun.net.httpserver.HttpsParameters` wasn't matching the API specification. The commit in this PR fixes that issue and it now matches the API specification as well as what is done in `javax.net.ssl.SSLParameters` class.

Additionally, as noted in the JBS issue, the (internal class) `sun.net.httpserver.SSLStreams` had a bug where it could end up resetting the `needClientAuth` flag on the `SSLEngine` because of the way the `setNeedClientAuth()` and `setWantClientAuth()` methods were being called on the `SSLEngine`. This too has been fixed in this PR.

A new jtreg test has been introduced to reproduce the issue in the `HttpsParameters` class and verify this fix.

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Commit messages:
 - 8326381: com.sun.net.httpserver.HttpsParameters and SSLStreams incorrectly handle needClientAuth and wantClientAuth

Changes: https://git.openjdk.org/jdk/pull/17940/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=17940&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8326381
  Stats: 104 lines in 3 files changed: 100 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/17940.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/17940/head:pull/17940

PR: https://git.openjdk.org/jdk/pull/17940