getLiveRegion
Gets the node's live region mode.
A live region is a node that contains information that is important for the user and when it changes the user should be notified. For example, in a login screen with a TextView that displays an "incorrect password" notification, that view should be marked as a live region with mode ACCESSIBILITY_LIVE_REGION_POLITE.
It is the responsibility of the accessibility service to monitor TYPE_WINDOW_CONTENT_CHANGED events indicating changes to live region nodes and their children.
Return
The live region mode, or ACCESSIBILITY_LIVE_REGION_NONE if the view is not a live region.