Convert ol.ObjectEvent#getKey method into key property

src/ol/object.js

@@ -33,6 +33,7 @@ ol.ObjectEventType = {
  * @param {string} type The event type.
  * @param {string} key The property name.
  * @extends {goog.events.Event}
+ * @implements {oli.ObjectEvent}
  * @constructor
  */
 ol.ObjectEvent = function(type, key) {
@@ -41,23 +42,13 @@ ol.ObjectEvent = function(type, key) {
   /**
    * The name of the property whose value is changing.
    * @type {string}
-   * @private
    */
-  this.key_ = key;
+  this.key = key;
 
 };
 goog.inherits(ol.ObjectEvent, goog.events.Event);
 
 
-/**
- * Get the name of the property associated with this event.
- * @return {string} Object property name.
- */
-ol.ObjectEvent.prototype.getKey = function() {
-  return this.key_;
-};
-
-
 
 /**
  * @constructor
@@ -277,7 +268,7 @@ ol.Object.prototype.createBeforeChangeListener_ = function(key, targetKey) {
    * @this {ol.Object}
    */
   return function(event) {
-    if (event.getKey() === targetKey) {
+    if (event.key === targetKey) {
       this.dispatchEvent(
           new ol.ObjectEvent(ol.ObjectEventType.BEFOREPROPERTYCHANGE, key));
     }