i am thinking that is unrelated to the back brakes. You shouldn't have gotten air that far up the system to get pushed into the fronts. Even if there was a bit of air in the fronts i don't presume it would make for dragging brakes.
I would take off your front calipers and clean/lube the sliders. most dragging issues come from that. i cooked a rotor and pad recently because of mud drying out between the caliper and support. couldn't slide, and just went down hill as things warmed up.