Salt turkey after wet brine?

I got a turkey breast for Thanksgiving. It turned out to be frozen, though I called the butcher, who assured me that it is not frozen all the way through. I had intended to do a dry brine, but that was impossible because it was still rock solid on the surface. I decided to through it in a wet brine to thaw and brine at the same time. I've never done a wet brine like this before. Will the turkey end up salty enough from the brine or should I add some salt before roasting? I have searched and searched and haven't come up with an answer! If it makes a difference, I am planning on rubbing it with herb butter before roasting.