8267529: StringJoiner can create a String that breaks String::equals

[cl4es]

This patch fixes a regression caused by https://bugs.openjdk.java.net/browse/JDK-8265237 where the result of String.join always get a UTF-16 coder if the delimiter is UTF-16, even when no delimiter is emitted.

---

Progress

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Issue

• JDK-8267529: StringJoiner can create a String that breaks String::equals

Reviewers

• Naoto Sato (@naotoj - Reviewer) ⚠️ Review applies to 0e2ca7c

Reviewing

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[openjdk]

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[mlbridge]

Webrevs

• 01: Full - Incremental (b4b9d14d)
• 00: Full (0e2ca7cd)

[openjdk]

@cl4es This change now passes all automated pre-integration checks.

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

8267529: StringJoiner can create a String that breaks String::equals

Reviewed-by: naoto

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[cl4es]

Thanks for reviewing, Naoto

/integrate

[openjdk]

@cl4es Since your change was applied there have been 3 commits pushed to the master branch:

• 7f52c50: 8182043: Access to Windows Large Icons
• 8a31c07: 8267886: ProblemList javax/management/remote/mandatory/connection/RMIConnector_NPETest.java
• ae258f1: 8265418: Clean-up redundant null-checks of Class.getPackageName()

Your commit was automatically rebased without conflicts.

Pushed as commit 95b1fa7.

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