[jdk11u-dev] RFR: 8261351: Create implementation for NSAccessibilityRadioButton protocol

[Autumn Capasso]

Backport https://bugs.openjdk.org/browse/JDK-8261351. Clean backport, on of 28 https://bugs.openjdk.org/browse/JDK-8152350.

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Commit messages:
 - Backport 6badd22e664696fb7119b1cc9b89cf719edfb92f

Changes: https://git.openjdk.org/jdk11u-dev/pull/1642/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1642&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8261351
  Stats: 77 lines in 3 files changed: 76 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1642.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev pull/1642/head:pull/1642

PR: https://git.openjdk.org/jdk11u-dev/pull/1642