warning in cron re transients

The following web server warning is regularly logged:

PHP Warning: Invalid argument supplied for foreach() in /myhome/wordpress/wp-content/plugins/conversation-watson/includes/api.php on line 205, referer: https://mysite.com/wp-cron.php?doing_wp_cron=something.somethingelse

It would be nice if your code were to check for transients before cluttering up needlessly the log with warnings, in case there aren’t any.