8251858: Update to Xcode 11.3.1

[kevinrushforth]

This updates the compiler used to build JavaFX on macOS to Xcode 11.3.1 + MacOSX10.15 sdk, which matches the compiler used to build JDK 16.

As noted in the bug report, Xcode 11.3.1 needs macOS 10.14.4 (Mojave) or later to build, but the produced artifacts will be able to run on earlier versions of macOS.

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Progress

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

Issue

• JDK-8251858: Update to Xcode 11.3.1

Reviewers

• Johan Vos (jvos - Reviewer)
• Ambarish Rapte (arapte - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jfx pull/291/head:pull/291
$ git checkout pull/291

[kevinrushforth]

/reviewers 2

[bridgekeeper]

👋 Welcome back kcr! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request.

[openjdk]

@kevinrushforth
The number of required reviews for this PR is now set to 2 (with at least 1 of role reviewers).

[mlbridge]

Webrevs

• 00: Full (703403f)

[arapte]

Build verified on Mojave 10.14.6

[openjdk]

@kevinrushforth This change now passes all automated pre-integration checks. When the change also fulfills all project specific requirements, type /integrate in a new comment to proceed. After integration, the commit message will be:

8251858: Update to Xcode 11.3.1

Reviewed-by: jvos, arapte

• If you would like to add a summary, use the /summary command.
• To credit additional contributors, use the /contributor command.
• To add additional solved issues, use the /issue command.

There are currently no new commits on the master branch since the last update of the source branch of this PR. If another commit should be pushed before you perform the /integrate command, your PR will be automatically rebased. If you would like to avoid potential automatic rebasing, specify the current head hash when integrating, like this: /integrate 88c0f97876e94dbd932848094b43c6305930b873.

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

[kevinrushforth]

/integrate

[openjdk]

@kevinrushforth
Pushed as commit 87ad57f.