Pretty sure you still need them. One resistor is to simulate the load of the filament bulb to get rid of the bulb out message. The second resistor is so the the LED bulbs works at 2 brightness levels so when you use the brake at night or with the running lights, the brakes will go from dim to fully bright like they are suppose to. Without the resistor to dim the led bulbs, the led bulb will be at maximum brightness with the running light or low beams on, without pressing the brakes, so when you actually press the brake, the brightness doesn't change because its already at it's maximum.
If you dont want to warm the cars behind you that you're braking, you dont need the resistors.