8318915: Enhance checks in BigDecimal.toPlainString()

[GoeLin]

I backport this for parity with 17.0.16-oracle.

Fixed build. AbstractStringBuilder.repeat(...) is not in 17.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• JDK-8318915 needs maintainer approval
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8318915: Enhance checks in BigDecimal.toPlainString() (Enhancement - P3 - Requested)

Reviewers

• Paul Hohensee (@phohensee - Reviewer)

Reviewing

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$ git checkout pull/3510

Update a local copy of the PR:
$ git checkout pull/3510
$ git pull https://git.openjdk.org/jdk17u-dev.git pull/3510/head

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$ git pr checkout 3510

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Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back goetz! A progress list of the required criteria for merging this PR into master 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.

[mlbridge]

Webrevs

• 00: Full (016ccea9)

[openjdk]

⚠️ @GoeLin This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[GoeLin]

Thanks for the review!