[jdk17u-dev] RFR: 8342075: HttpClient: improve HTTP/2 flow control checks

[Goetz Lindenmaier]

I backport this for parity with 17.0.17-oracle.

src/java.net.http/share/classes/jdk/internal/net/http/Stream.java
Two trivial resolves due to context.

src/java.net.http/share/classes/jdk/internal/net/http/WindowUpdateSender.java

Resolved because 8308310: HttpClient: Avoid logging or locking from within synchronized blocks
is not in 17.

src/java.net.http/share/classes/module-info.java
Omitted, as "8296804: Document HttpClient configuration properties in java.net.http module-info"
is not in 17.  The CSR for 17 documents that this is dropped.

Follow ups are on the list of backports I will do.
Blocking changes all already in 17.

I had to adapt ConnectionFlowControlTest.java and StreamFlowControlTest.java because HttpClient does not
implement AutoClosable / shutdownNow() / close() in 17.
I also amended the @build instructions in StreamFlowControlTest.java.

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Commit messages:
 - Merge branch 'openjdk:master' into goetz_backport_8342075
 - Make tests compile
 - Resolved changes
 - Backport 32ac3e713ea4370e496717967fff7de9450d2f69
 - backport 209939a90e9b804da4c37ebd978b088cb8f41ead

Changes: https://git.openjdk.org/jdk17u-dev/pull/3786/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=3786&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8342075
  Stats: 1025 lines in 12 files changed: 992 ins; 2 del; 31 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/3786.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/3786/head:pull/3786

PR: https://git.openjdk.org/jdk17u-dev/pull/3786