“Flower Drum Song” is a San Francisco story, but it changed a lot on its way back to the Bay Area. Originally a 1957 novel by Chinese-American author C.Y. Lee and set in San Francisco, it quickly was turned into a 1958 Broadway musical by Rodgers and Hammerstein. After being adapted into a 1961 film, the musical fell into disuse, considered condescending and stereotype-ridden despite the creators’ best intentions.