client/splunk.ui.charting.js
function (eventType, handler) {
		// simplest possible event model for internal use
		this.element['on' + eventType] = function () {
			var evt = win.event;
			evt.target = evt.srcElement;
			handler(evt);
		};
		return this;
	}
function (eventType, handler) {
		// simplest possible event model for internal use
		this.element['on' + eventType] = function () {
			var evt = win.event;
			evt.target = evt.srcElement;
			handler(evt);
		};
		return this;
	}
function ( eventType , handler ) { // simplest possible event model for internal use
 this . element [ 'on' + eventType ] = function ( ) { var evt = win . event ; evt . target = evt . srcElement ; handler ( evt ) ; } ; return this ; }
Add an event listener. VML override for normalizing event parameters.
@param {String} eventType
@param {Function} handler
Add an event listener . VML override for normalizing event parameters .