Unless your chicken was badly contaminated before it was frozen,or you're planning to make chicken tartare :-), you'll be just fine. Why? Bacterial growth is a (nonlinear) function of temperature. From Modernist Cuisine, at a constant temperature of 68 degrees (the chicken's surface temp that is) it takes 18 hours to reach unsafe levels of salmonella. And your chicken's was likely considerably colder for much of the resting time. The "4 hours at room temperature" that is often quoted is assuming a worst case of a room temperature of 107 degrees and a food item that's already at that temperature.