Description

Some keyboard accessibility issues had crept into the Block Navigation in its form on the Navigation Screen.

This PR fixes an issue with the Block Navigation's Block Settings menu. Roving tab index and arrow key navigation should now work again with this component.

It also makes the relationship between TreeGridCell and the various components used in the BlockNavigation clearer by explicitly declaring the forwarded props individually rather than by spreading them as ...props.

How has this been tested?

1. Visit the Navigation Menu screen and build a menu
2. Tab into the Block Navigation panel and use arrow keys to move around it
3. Expect that arrow keys should behave as though navigating within a grid
4. Focus the Block Settings Menu toggle button in the Block Navigation
5. Press the down arrow.
6. Expect that the menu did not open and focus was moved to the settings menu on the next row.
7. Press Shift + Tab
8. Expect that focus left the Block Navigation Menu
9. Press Tab
10. Expect that focus moved back to the element that was last focused within Block Navigation.

Types of changes

Bug fix (non-breaking change which fixes an issue)

Checklist:

• My code is tested.
• My code follows the WordPress code style.
• My code follows the accessibility standards.
• My code has proper inline documentation.
• I've included developer documentation if appropriate.
• I've updated all React Native files affected by any refactorings/renamings in this PR.