STOCKTON — A Sonoma County sheriff’s deputy and his canine partner, Titan, spot a threatening man peering out from inside a port-a-potty.As Titan sprints toward danger without hesitation, the man emerges screaming and waving a pack of plastic jugs. The lean and powerful German shepherd leaps into the air and bites down hard on the man’s left arm while refusing to let go.In reality, no one was hurt or in any serious danger.