SEOUL, South Korea — Responding to threats of boycotts and picket lines, Warner Bros. Korea has canceled its scheduled release of “Falling Down” because movie critics here say the pic promotes racial violence, company officials said Wednesday.The Michael Douglas starrer, scheduled for release in Seoul next week, includes a scene in which a Korean grocer, accused of overcharging for a can of soda, is beaten and his store destroyed by an assailant with a baseball bat. Seoul’s YMCA had threatened to picket movie theaters and launch a boycott against all Warner Bros. releases. “In response to the protests by South Koreans, we have decided not to release the movie,” a company official said in a telephone interview. He spoke on condition of anonymity. The U.S. film company had hoped to release “Falling Down” after editing out references to Koreans. Activists charged that even with those scenes cut out, the movie remains racist and promotes racial violence.