[a11y] [macos] In Optionpane Demo, inside ComponentDialog Example, unable to navigate to all items, with VO on

In Optionpane Demo, inside ComponentDialog Example, unable to navigate to all items, with VO on.

Steps to reproduce:
1. Run SwingSet2.jar from demos.
2. Navigate to OptionPaneDemo.
3. Navigate to Component Dialog Example.
4. Try navigating to different items in the ComboBox.
5. The focus is only on the first item, and it does not goto other items.

Expected:
It should be possible to navigate to other items in the ComboBox and possible to select any one of them.