It’s been 20 years since Cake emerged on the local music scene, at first playing every tiny venue from Old Ironsides to Java City. Now Conan O’Brien and Jon Stewart are fans, and their songs are being used by the likes of Jay-Z and Apple. With the band’s first new album in seven years coming out this January, we take a peek inside the rock ’n’ roll lifestyle of Sacramento’s unlikeliest pop stars.