A Mexican-themed drinking party promoted by employees of the student-run Coffee House at UC Davis has roiled the campus, threatening to ignite racial tensions even as the university ramps up admission for minorities and international students. Clad in red T-shirts and chanting slogans, about 100 UC Davis students participated Friday in a sit-in at the Coffee House, urging a boycott of the cafeteria. The protest came after some Coffee House employees promoted an off-campus party at a local park Saturday that they dubbed “Cinco de Drinko,” a name university leaders said had strong connotations of racism. The Facebook event page...