The state of California has taken a major step toward phasing out gas-powered vehicles, and Massachusetts is following suit. By 2035, all new cars sold in the state must run on electric or hydrogen power, after Governor Baker signed a climate change law earlier this month. The law includes a trigger, according to experts, that says that once California decided to implement zero-emission vehicles, Massachusetts must do the same. Since California made that decision Thursday, regulators here must now begin to work on the details and put auto dealers, along with the public, on notice that the change will be...