[jdk17u-dev] RFR: 8280124: Reduce branches decoding latin-1 chars from UTF-8 encoded bytes

[Boris Ulasevich]

Backport e314a4cfda30cc680b3f0aef8c62b75ff81bdbb1

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Commit messages:
 - Backport e314a4cfda30cc680b3f0aef8c62b75ff81bdbb1

Changes: https://git.openjdk.org/jdk17u-dev/pull/658/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=658&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8280124
  Stats: 139 lines in 2 files changed: 93 ins; 34 del; 12 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/658.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev pull/658/head:pull/658

PR: https://git.openjdk.org/jdk17u-dev/pull/658