RFR: 8185429: [macos] After the dialog is closed, there is no window become active

[Alisen Chung]

Add a check for previous focused window on modal unblocking. If the owner of a closing dialog was the last focused window, then the owner of the dialog should regain focus.

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Commit messages:
 - update copyright years
 - init commit

Changes: https://git.openjdk.org/jdk/pull/19588/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19588&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8185429
  Stats: 8 lines in 2 files changed: 6 ins; 1 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/19588.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19588/head:pull/19588

PR: https://git.openjdk.org/jdk/pull/19588