The consensus on electro and plated pieces seems to be that intact plating is not affected, but that already compromised, separating areas may be. If there is a concern of affecting it, lye is safe on plating, so you could de-crud with it, and then follow upon any rust with vinegar/water and steel wool.
I once re-habbed a Griswold DuChro chicken fryer as a favor to a flea market vendor. The outside had some pinpoint rust spots; the inside was rusted to the point of deep pitting. With little to lose, I put it thru electro with the inside facing the anode. It de-rusted fine, and the plating did not seem to suffer any more than it already had.