Pour the olive oil into a skillet over medium-high heat; cook the onion and garlic in the oil until the onions are translucent, 2 to 3 minutes; add the chicken and cook about 30 seconds while stirring. Stir in the curry paste until the chicken is evenly coated. Pour the chutney and tomatoes into the pan; continue to cook until the chicken breasts are no longer pink in the center and the juices run clear, about 10 minutes.