Updates to (recently added) keyboarding events + add ability to have split buttons on macOS

[nakambo]

Please select one of the following

• I am removing an existing difference between facebook/react-native and microsoft/react-native-macos 👍
• I am cherry-picking a change from Facebook's react-native into microsoft/react-native-macos 👍
• I am making a fix / change for the macOS implementation of react-native
• I am making a change required for Microsoft usage of react-native

Summary

• Switch key down and key up to direct events. Because views need to specify what events they're interested in, they should probably only receive those events (and nothing else). But because these were added as bubbling events, views can receive events they never asked for, since these events "bubbled" (to their ancestors, from the RN side, not the native\OS side -- which makes sense on say, Win32, where there's no such specification on what events views are interested in, but not so much on the Mac)
• Fix wrong keyUp -> keyDown redirection in RCTView
• Minor fixes in keyboard events example to test the above
• Add custom accessibility role override + actions on button. Plumb to underlying touchable.
• Add new accessibility roles (menu button, pop up button)
• Add new custom split button example that demonstrates possible usage of the above

Test Plan

• Tested various keys on the button (g, h, i, x, j, k, l) and the enclosing view (a, b, c, d, x, left arrow, right arrow). Ensured there are no "duplicate" events
• Tested VO with the custom split button example -- checked role, accessibility hint, press (VO+space), and show menu (VO+shift+m) actions
• The above, this time with accessibility inspector instead
• Ensured no new warnings in RNTester

Microsoft Reviewers: Open in CodeFlow

[pull-bot]

Messages

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