At the beginning of the year, efforts to put driverless cars on California's streets looked like they were careening. Uber had defied state officials by failing to get permits to test its technology and then the company shipped its cars to Arizona to test them there. After four years of trying, regulators were still trying to write rules for testing cars without anyone in the driver's seat. Lawmakers and tech industry representatives worried that California was losing its grip on innovation in a sector primed for growth. Now, after this year's release of guidelines from the state Department of Motor Vehicles, the mood has changed.