title: html5 number field distinguish event if value increase or decrease
body: <p>I am using HTML5 number field to set top Position , when number field is increased with up [inside number field] i need to increase the top value vice versa if it is decrease then need to decrease top value.</p>
  
  <pre><code>$("#font_y_pos").change(function(event) {
  var obj = canvas.getActiveObject();
  
  if (!obj)
      return;
  
  var y_pos = obj.getTop() - $(this).val();
  obj.set('top', y_pos);
  canvas.renderAll();
                 });
  </code></pre>
  
  <p>but how can i distinguisg this 2 event ??? if value is increased or decreased?</p>