A couple of missed cases of removing AppContext from Swing UI classes and one dead import
------------- Commit messages: - 8378204 Changes: https://git.openjdk.org/jdk/pull/29806/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29806&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8378204 Stats: 14 lines in 3 files changed: 0 ins; 11 del; 3 mod Patch: https://git.openjdk.org/jdk/pull/29806.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/29806/head:pull/29806 PR: https://git.openjdk.org/jdk/pull/29806
