8269131: Update libxml2 to version 2.9.12

[kevinrushforth]

Clean backport of third-party update to libxml2 2.9.12.

As an FYI, I tested this patch in my test-kcr-11.0.13 branch, which has the aggregate set of patches for the following bugs: JDK-8211308, JDK-8268915, JDK-8269147, JDK-8269131, JDK-8268849, JDK-8270479, JDK-8272329.

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Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8269131: Update libxml2 to version 2.9.12

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jfx11u pull/33/head:pull/33
$ git checkout pull/33

Update a local copy of the PR:
$ git checkout pull/33
$ git pull https://git.openjdk.java.net/jfx11u pull/33/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 33

View PR using the GUI difftool:
$ git pr show -t 33

Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jfx11u/pull/33.diff

[bridgekeeper]

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[openjdk]

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

[openjdk]

@kevinrushforth This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8269131: Update libxml2 to version 2.9.12

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 1 new commit pushed to the master branch:

• 1a021ed: 8209086: Some javafx.web files are missing GPLv2+Classpath copyright header

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[mlbridge]

Webrevs

• 00: Full (ff6c3e05)

[kevinrushforth]

/integrate

[openjdk]

Going to push as commit f930bc5.
Since your change was applied there have been 3 commits pushed to the master branch:

• 49ff8f6: 8269147: Update GStreamer to version 1.18.4
• ebc5926: 8268915: WebKit build fails with Xcode 12.5
• 1a021ed: 8209086: Some javafx.web files are missing GPLv2+Classpath copyright header

Your commit was automatically rebased without conflicts.

[openjdk]

@kevinrushforth Pushed as commit f930bc5.

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