British indie-pop revivalists Allo Darlin’ are the band for you if you like softly sung vocals, jangly guitars and tempos that will get you turned up enough to drink tea with your cat. Their third album continues in this mild fashion, and though always pleasant, it’s often unmemorable. The band, which on past albums has sung odes to Polaroid cameras and Nineties hits, seems obsessed with nostalgia. The highlight is “History Lessons,” about living in the present: “What came before doesn’t have to have been the best,” sings frontwoman Elizabeth Morris. It wouldn’t hurt the group to take its own advice.