RFR: 8315655: [macos] Right click and dragging over a component with a popup menu will open the popup

[Alisen Chung]

Issue is a mouse drag will trigger a popup in macos, but not in linux or windows.
The solution is to add a check for a mouse pressed event to show popup and prevent mouse entered events from triggering the popup

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Commit messages:
 - fix trailing whitespace in instructions string
 - fix line ender
 - fix whitespaces and newline
 - fix whitespaces and newline
 - init commit

Changes: https://git.openjdk.org/jdk/pull/19569/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19569&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8315655
  Stats: 85 lines in 2 files changed: 84 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/19569.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19569/head:pull/19569

PR: https://git.openjdk.org/jdk/pull/19569