var map;

function initMap() {
    map = new google.maps.Map(document.getElementById("map"), {
        zoom: 5,
        center: new google.maps.LatLng(35.713819, 139.7598354)
    });
    infowindow = new google.maps.InfoWindow({ content: 'Test' });
    google.maps.event.addListener(map, 'click', function() {
        infowindow.close(map);
    });
    refreshMarkers();
}