src/utils.js
function(event, property, value) {
    try {
      Object.defineProperty(event, property, {
        get : function() {
          return value;
        }
      });
    } catch(e) {
      event[property] = value;
    }
  }
function(event, property, value) {
    try {
      Object.defineProperty(event, property, {
        get : function() {
          return value;
        }
      });
    } catch(e) {
      event[property] = value;
    }
  }
function ( event , property , value ) { try { Object . defineProperty ( event , property , { get : function ( ) { return value ; } } ) ; } catch ( e ) { event [ property ] = value ; } }
Set event property with a Chromium specific hack
Set event property with a Chromium specific hack