Well, the law also says "upon a highway"...which seems in line with my observations that I only ever see minimum speed limits posted on highways. It sounds to me like the google vehicle was in compliance with the law.
"360. "Highway" is a way or place of whatever nature, publicly
maintained and open to the use of the public for purposes of
vehicular travel. Highway includes street."
"360. "Highway" is a way or place of whatever nature, publicly maintained and open to the use of the public for purposes of vehicular travel. Highway includes street."
http://www.leginfo.ca.gov/cgi-bin/displaycode?section=veh&gr...