RFR: Merge jdk17 [v2]

[Daniel Fuchs]

On Mon, 14 Jun 2021 15:58:15 GMT, Jesper Wilhelmsson <jwilhelm at openjdk.org> wrote:

>> Forwardport JDK 17 -> JDK 18
>
> Jesper Wilhelmsson 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.

Looked at this two changesets and they were fine.
 - 8268342: java/foreign/channels/TestAsyncSocketChannels.java fails with "IllegalStateException: This segment is already
 - 8268555: Update HttpClient tests that use ITestContext to jtreg 6+1

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Marked as reviewed by dfuchs (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/4484