If rock'n'roll owns a season, summer is definitely it. Maybe not in the city, where the low throb of hip-hop rules the streets, but at the state fair, where the Matterhorn blasts Aerosmith and Pearl Jam. And in sun-baked stadiums, where tan boys and girls tuck their T-shirts in their belts and stagedive into swirls of dust. Come summertime, rock'n'roll is mating-call and calling- card, bearing the promise of blue skies, cold beer, and hot dates, eternally.The Breeders' second album spins out as a litany of summer — or rather, a summer of rock'n'roll. Its bright cymbal sound flashes off submerged lyrics about sunshine and water and steaming metal; the broiling guitars reek occasionally of surf.