This past summer, instead of strapping on bags filled with water bottles, sandwiches and trail mix, Google staffers slipped on backpacks outfitted with Google Trekkers, a strange blue sphere that hovers above one’s head and has big cut-outs for cameras that snap photos in all directions every few seconds. The employees hiked in 14 of California’s state parks, including Samuel P. Taylor, Tomales Bay State Park, Mount Tamalpais and China Camp. Thousands of images were…