Add Map postrender event

src/ol/base/map.js

@@ -2,9 +2,9 @@
 // FIXME recheck layer/map projection compatability when projection changes
 // FIXME layer renderers should skip when they can't reproject
 // FIXME add tilt and height?
-// FIXME add postrender event
 
 goog.provide('ol.Map');
+goog.provide('ol.MapEventType');
 goog.provide('ol.MapProperty');
 
 goog.require('goog.array');
@@ -40,6 +40,14 @@ goog.require('ol.Size');
 goog.require('ol.TransformFunction');
 
 
+/**
+ * @enum {string}
+ */
+ol.MapEventType = {
+  POST_RENDER: 'postrender'
+};
+
+
 /**
  * @enum {string}
  */