Add a notification of each type to each customizer setting: paste this into your console

notifications-test.js

wp.customize.each( function( setting ) { 
	var notifications = [
		new wp.customize.Notification( 'example-error', { 'message': 'This is an example error.', type: 'error' } ),
		new wp.customize.Notification( 'example-warning', { 'message': 'This is an example warning.', type: 'warning' } ),
		new wp.customize.Notification( 'example-info', { 'message': 'This is an example info.', type: 'info' } ),
		new wp.customize.Notification( 'example-notice', { 'message': 'This is an example notice.', type: 'notice' } ),
	];
	_.each( notifications, function ( notification ) {
		setting.notifications.add( notification.code, notification );
	} );
} );