I hope I understood you right, but the easiest way to get that result is using a shorthand if/else-statement (which is already being used in that line of code).
do_shortcode( $wpautop_value == 'true' ? wpautop($text) : $text )
or the full line of code:
$text = (!$text && !$title) ? '<p><strong>TextBox</strong> » Add Content!</p>' : sprintf('<div class="hentry">%s</div>', do_shortcode( $wpautop_value == 'true' ? wpautop($text) : $text ) );