The message reads "(2) virus have been detected on you Samsung Galaxy S4 and battery has been infected and damaged". I received this message while on the internet.
More than likely it was an ad masquerading as a virus. As long as you didn't click OK to the prompts and let it download stuff, you should hopefully be OK.
If you want to make sure, you could download an Antivirus /Anti-Malware app to be sure.