マップビュー上に新しいボタンを追加することで、1つの方法で行うことができます。
let googleButton = UIButton(type: UIButtonType.custom) as UIButton
googleButton.setImage(UIImage(named: "RecenterButton"), for: .normal)
googleButton.frame = CGRectMake(self.view.frame.size.width-60, 100, 50, 50)
googleButton.addTarget(self, action: #selector(boundPosition), forControlEvents: .TouchUpInside)
self.view.addSubview(googleButton)
self.view.sendSubviewToBack(mapView)
func boundPosition() {
let loc = CLLocationCoordinate2D(latitude: latitude, longitude: longitude)
let bounds = GMSCoordinateBounds(coordinate: loc, coordinate: loc)
mapView.animateWithCameraUpdate(GMSCameraUpdate.fitBounds(bounds, withPadding: 20.0))
mapView.animateToZoom(15)
mapView.animateToViewingAngle(70)
}