A San Francisco police officer stands in front of a Google commuter bus after clearing demonstrators blocking its path in the Mission District in San Francisco, California August 1, 2014. The bus was blocked by protesters, highlighting many residents' growing concern that an influx of affluent technology workers is driving up costs in the city. REUTERS/Robert Galbraith (UNITED STATES - Tags: SOCIETY CIVIL UNREST POLITICS SCIENCE TECHNOLOGY REAL ESTATE BUSINESS)