<i18n dev> RFR: 8293008: Replace uses of StringBuffer with StringBuilder in MergeCollation

[Roger Riggs]

On Wed, 24 Aug 2022 19:31:23 GMT, Andrey Turbanov <aturbanov at openjdk.org> wrote:

> Couple of package-private classes in `java.text` package still use `StringBuffer`: `MergeCollation` and `PatternEntry`.
> StringBuffer is a legacy synchronized class. StringBuilder is a direct replacement to StringBuffer which generally have better performance.

LGTM

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Marked as reviewed by rriggs (Reviewer).

PR: https://git.openjdk.org/jdk/pull/10007