RFR: 8377192: Remove AppContext from MenuSelectionManager

[Phil Race]

remove AppContext from Swing's MenuSelectionManager

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Commit messages:
 - 8377192

Changes: https://git.openjdk.org/jdk/pull/29579/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29579&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8377192
  Stats: 24 lines in 2 files changed: 0 ins; 21 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/29579.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29579/head:pull/29579

PR: https://git.openjdk.org/jdk/pull/29579