code: function loadImage(url, callback, context) {
      if (url) {
        var img = new Image();
        /** @ignore */
        img.onload = function () {
          callback && callback.call(context, img);
          img = img.onload = null;
        };
        img.src = url;
      }
      else {
        callback && callback.call(context, url);
      }
    }
docs: Loads image element from given url and passes it to a callback
  @method loadImage
  @memberOf fabric.util
  @param {String} url URL representing an image
  @param {Function} callback Callback; invoked with loaded image
  @param {Any} context optional Context to invoke callback in