RFR: 8326949: Authorization header is removed when a proxy Authenticator is set on HttpClient [v14]

[Michael McMahon]

> Hi,
> 
> I closed https://github.com/openjdk/jdk/pull/21249 and am continuing the review on this PR.
> 
> This fix relaxes the constraints on user set authentication headers. Currently, any user set authentication headers are filtered out, if the HttpClient has an Authenticator set. The reason being that the authenticator is expected to manage authentication. With this fix, it will be possible to use pre-emptive authentication through user set headers, even if an authenticator is set. The expected use case is where the authenticator would manage either proxy or server authentication and the user set headers would manage server authentication if the authenticator is managing proxy (or vice versa).
> 
> A CSR will be filed to document this change.
> 
> Thanks,
> Michael

Michael McMahon 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 19 additional commits since the last revision:

 - Merge branch 'master' into 8326949-authorize-v2
 - added final test scenario
 - Merge branch 'master' into 8326949-authorize-v2
 - test update
 - Fixed test case and updated API doc
 - update
 - Merge branch 'master' into 8326949-authorize-v2
 - updated apidoc
 - Merge branch '8326949-authorize-v2' of https://github.com/Michael-Mc-Mahon/jdk into 8326949-authorize-v2
 - Update src/java.net.http/share/classes/jdk/internal/net/http/Stream.java
   
   Co-authored-by: Daniel Jelinski <djelinski1 at gmail.com>
 - ... and 9 more: https://git.openjdk.org/jdk/compare/25b7f3ef...57584536

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/21408/files
  - new: https://git.openjdk.org/jdk/pull/21408/files/0a4ea8ad..57584536

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=21408&range=13
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=21408&range=12-13

  Stats: 88177 lines in 112 files changed: 87066 ins; 788 del; 323 mod
  Patch: https://git.openjdk.org/jdk/pull/21408.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21408/head:pull/21408

PR: https://git.openjdk.org/jdk/pull/21408