FabricJS - Rotate Object via Variable Name on Button Click

Using a button click, rotate an object on the FabircJS Canvas that is specified by a variable.

HTML

<script src="https://rawgit.com/kangax/fabric.js/master/dist/fabric.js"></script>
<script src="http://promincproductions.com/gaTrackingJSFiddle.js"></script>
<button id="add">Add</button>
<canvas id="c" width="640" height="360"></canvas>

CSS

canvas{
  border-width: 1pz;
  border-style: solid;
  border-color: #000;
}

JavaScript

var canvas = new fabric.Canvas('c');


$("#add").click(function(){
      var stockImageSrc = 'https://i.ytimg.com/vi/JphpLkmimVo/hqdefault.jpg';
        fabric.Image.fromURL(stockImageSrc, function (oImg) {
                        oImg.setWidth(640);
                        oImg.setHeight(390);
                        canvas.add(oImg); 
                        canvas.renderAll();
                    }, { crossOrigin: '' });
});