8283544: HttpClient GET method adds Content-Length: 0 header

[GoeLin]

I backport this for parity with 17.0.18-oracle.

Clean backport. Original change is in 19.

The test needed a small adaption to build, see extra commit.
HEAD() was only added by https://bugs.openjdk.org/browse/JDK-8276559 (httpclient) Consider adding an HttpRequest.Builder.HEAD method to build a HEAD request.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8283544 needs maintainer approval

Issue

• JDK-8283544: HttpClient GET method adds Content-Length: 0 header (Bug - P4)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk17u-dev.git pull/4162/head:pull/4162
$ git checkout pull/4162

Update a local copy of the PR:
$ git checkout pull/4162
$ git pull https://git.openjdk.org/jdk17u-dev.git pull/4162/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 4162

View PR using the GUI difftool:
$ git pr show -t 4162

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk17u-dev/pull/4162.diff

[bridgekeeper]

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[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.