Itext not update boundingrect when change google font weight and font style

by tinyhustlee

HTML

<script src="https://rawgit.com/kangax/fabric.js/master/dist/fabric.js"></script>
<script src="https://rawgit.com/bramstein/fontfaceobserver/master/fontfaceobserver.js"></script>
<style>
@import url('https://fonts.googleapis.com/css?family=Roboto:400,400i,700,700i');
</style>
<canvas id="c" style="width: 500px; height: 500px;"></canvas>

JavaScript

var canvas = new fabric.Canvas('c');
canvas.setDimensions({'width' : 500, 'height' : 500});
    var text = new fabric.IText('Font Weigh, Font Style', {
      left: 50,
      top: 50,
      width: 450,
      fontSize: 30,
      objectCaching: false,
      fontFamily: 'Roboto',
      fontStyle: 'italic',
      fontWeight: 'bold'
    });
    canvas.add(text).setActiveObject(text);
    
var myfont = new FontFaceObserver('Roboto')
  myfont.load()
    .then(function() {
      canvas.renderAll();
    }).catch(function(e) {
      console.log(e)
      alert('font loading failed ' + font);
});