问如何禁用知道您的位置弹出窗口

EN

var usermarkers = [];
var userMarker;

function geolocation() {
    if (navigator.geolocation) {
        navigator.geolocation.getCurrentPosition(function (position) {

            userLat = position.coords.latitude;
            userLng = position.coords.longitude;

            currentloc = { lat: userLat, lng: userLng };

            var userSerial = "987654321";

            for (var i = 0; i < usermarkers.length; i++) {
                if (usermarkers[i].serialNumber === userSerial) {
                    usermarkers[i].setMap(null);
                    usermarkers = [];
                }
            }

            userMarker = new google.maps.Marker({
                position: currentloc,
                map: map,
                serialNumber: userSerial
            });
            userMarker.setIcon('http://maps.google.com/mapfiles/ms/icons/green-dot.png')
            usermarkers.push(userMarker);

            calculateDistance(ppath);
        });
    } else {
        alert("Error: Your browser doesn\'t support geolocation.");

    }
}