I believe that is a standard part of the testing process. I remember seeing a 777 doing the same thing - an aborted takeoff then continues to the end of the runway with brakes on full, against engine power. The brakes caught on fire and burst the tires but they have to be able to taxi clear of the runway and last 5 mins or so on fire before the fire appliances in attendance are allowed to put them out.
Just found this...
http://www.youtube.com/watch?v=l5N2uBqJbVU