gistfile1.js

function Geolocator (modernizr, jquery, fallbackApi) {
    this.jquery = jquery;
    this.modernizr = modernizr;
    this.fallbackApi = fallbackApi;

}

Geolocator.prototype.is64BitFirefox = function () {
    var pattern = /.+Ubuntu.+Linux x86_64.+Firefox.+$/;
    var match = navigator.userAgent.match(pattern);
    console.log(this.modernizr.geolocation);
    if (match != null) {
        return true;
    }
    return false;
}

Geolocator.prototype.getLocation = function (options) {
    if (!this.modernizr.geolocation || this.is64BitFirefox()) {
        this.jquery.ajax({
            type: "GET",
            url: this.fallbackApi,
        })
        .done(function(data) {

            var result = {
                'latitude': data.latitude,
                'longitude': data.longitude
            };

            options.success(result);
        })
        .fail(options.error)
        ;
    } else {
        navigator.geolocation.getCurrentPosition(
            function (data) {
                options.success(data.coords);
            },
            options.error
        );
    }
};

// Example use

var gloc = new Geolocator(
                    Modernizr,
                    $,
                    'http://freegeoip.net/json/'
                );

gloc.getLocation({
                success: function (point) {
// returned point will have latitude and longitude properties

                    console.log(point);
                },
                error: function (data) {
                    console.log(data);
                    alert('Error');
                }
            });