GA+ has WP_DEBUG __construct() message on WP 4.3.0

I narrowed it down and Google Analytics+ version 3.1.5 is causing this WP_DEBUG message on WordPress version 4.3.0:

Notice: The called constructor method for WP_Widget is deprecated since version 4.3.0! Use __construct() instead. in /wp-includes/functions.php on line 3457