8342075: HttpClient: improve HTTP/2 flow control checks

[alexeybakhtin]

Please review the backport of JDK-8342075

Almost clean backport except for the import section of src/java.net.http/share/classes/jdk/internal/net/http/Http2Connection.java

Requires JDK-8317808 [1] as a prerequisite to fixing the hanging of the new tests.

Also, new tests require Http2TestExchange::getConnectionKey() method added by JDK-8335181 [2].

test/jdk/java/net/httpclient/lib/jdk/httpclient/test/lib/http2/Http2TestExchange.java, test/jdk/java/net/httpclient/lib/jdk/httpclient/test/lib/http2/Http2TestExchangeImpl.java and test/jdk/java/net/httpclient/lib/jdk/httpclient/test/lib/http2/Http2TestServerConnection.java test classes are updated to add getConnectionKey() implementation

All jtreg tests for java.net.httpclient are passed

[1] - #1426
[2] - openjdk/jdk@720b446#diff-c18c2a070038409f25c08e13c174a95f33840e2deddcc29f6d8306de572a618b

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• JDK-8342075 needs maintainer approval
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change requires CSR request JDK-8350602 to be approved

Integration blocker

 ⚠️ Dependency #1426 must be integrated first

Issues

• JDK-8342075: HttpClient: improve HTTP/2 flow control checks (Bug - P4)
• JDK-8350602: HttpClient: improve HTTP/2 flow control checks (CSR)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u-dev.git pull/1428/head:pull/1428
$ git checkout pull/1428

Update a local copy of the PR:
$ git checkout pull/1428
$ git pull https://git.openjdk.org/jdk21u-dev.git pull/1428/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 1428

View PR using the GUI difftool:
$ git pr show -t 1428

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk21u-dev/pull/1428.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back abakhtin! A progress list of the required criteria for merging this PR into pr/1426 will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

At least one of the issues associated with this backport has a resolved CSR for a different version. As this means that this backport may also need a CSR, the csr label is being added to this pull request to signal this potential requirement. The command /csr unneeded can be used to remove the label in case a CSR is not needed.

[mlbridge]

Webrevs

• 00: Full (ec9d0ca6)