Report the role of ComposeSceneAccessible on macOS as PANEL

[m-sasha]

Report the role of ComposeSceneAccessible (only on macOS) and the root LayoutNode as PANEL, allowing them to be ignored when accessible elements are presented to the user.

Fixes https://youtrack.jetbrains.com/issue/COMPOSE-1398/Make-ComposePanel-transparent-to-accessibility

Testing

Run the app below on macOS, turn on VoiceOver and traverse the accessible elements via VoiceOver shortcuts (ctrl-opt-right/left). The selection should move correctly inside the ComposePanel into the Compose button.

fun main() {
    SwingUtilities.invokeLater {
        val frame = JFrame()
        val panel = JPanel(GridLayout(3, 1))
        frame.contentPane.add(panel)

        panel.add(JPanel().apply {
            add(JButton("Swing Button 1"))
        })
        panel.add(ComposePanel().apply {
            setContent {
                Column {
                    Button(onClick = {}) { Text("Compose Button") }
                }
            }
        })
        panel.add(JPanel(GridLayout(2, 1)).apply {
            add(JButton("Swing Button 2"))
        })
        frame.size = Dimension(400, 500)
        frame.isVisible = true
    }
}

This could be tested by QA

Release Notes

Fixes - Desktop

• When using ComposePanel inside a Swing application on macOS, VoiceOver will now correctly go into the ComposePanel when traversing accessible elements.