谷歌地图Ajax多个标记Json

我有一个如下:https://jsfiddle.net/inkedraskal/h35dz9qd/5/

我得到一个错误:不能分配给只读属性'__e3_'的0

我之前有一个for循环，它在for循环之后调用函数，但是jshint不接受它。现在我在使用Ajax，但我卡住了。我可以返回控制台中的对象以及第一个信息框的内容(参见console)，然后我得到一个错误。

js如下所示:(任何提示，技巧等将受到赞赏)

(function () {
    renderGoogleMap();

    function renderGoogleMap() {
        var start_point = new google.maps.LatLng(0, 0);
        // Creating a new map
        var map = new google.maps.Map(document.getElementById("locations-map"), {
            center: start_point,
            zoom: 6,
            mapTypeId: google.maps.MapTypeId.ROADMAP
        });

        // Creating a global infoWindow object that will be reused by all markers
        var infoWindow = new google.maps.InfoWindow();
        function setMarkerPoints(map,marker) {
            var bounds = new google.maps.LatLngBounds();
            // Looping through the JSON data
                // Creating a closure to retain the correct data, notice how I pass the current data in the loop into the closure (marker, data)

                $.ajax({
                   type: "GET",
                    url: 'https://raw.githubusercontent.com/roryheaney/jsonexample/master/locatoins.json',
                    dataType: "json",
                    success: function (data) {
                        console.log(data);
                        if (data.length !== 0) {
                         var   latLng = new google.maps.LatLng(data.lat, data.lng);
                        // Creating a marker and putting it on the map
                        var marker = new google.maps.Marker({
                            position: latLng,
                            map: map,
                            title: data.title
                        });

                            $.each(data, function (marker, data) {
                                var windowContent = '<h3>' + data.title + '</h3>' +
                                    '<p>' + data.description + '</p>';
                                console.log(windowContent);
                                // Attaching a click event to the current marker
                                infobox = new InfoBox({
                                    content: infoWindow.setContent(windowContent),
                                    alignBottom: true,
                                    pixelOffset: new google.maps.Size(-160, -45)
                                });
                                google.maps.event.addListener(marker, 'click', function () {
                                    // Open this map's infobox
                                    infobox.open(map, marker);
                                    infobox.setContent(windowContent);
                                    map.panTo(marker.getPosition());
                                    infobox.show();
                                });
                                google.maps.event.addListener(map, 'click', function () {
                                    infobox.setMap(null);
                                });
                            });
                        } 

                    },
                    error: function (data) {
                        // alert('Please refresh the page and try again');
                        console.log('Please refresh the page and try again');
                    }
                });
                //END MARKER DATA

                // bounds.extend(marker.getPosition());
            // end loop through json
            map.setCenter(start_point);
            map.fitBounds(bounds);
        }
        setMarkerPoints(map);
    }
})();