Delegate the onRender function to the correct property

lib/timeline/Core.js

@@ -254,6 +254,13 @@ Core.prototype.setOptions = function (options) {
       }
     }
 
+    // if the graph2d's drawPoints is a function delegate the callback to the onRender property
+    if (typeof options.drawPoints == 'function') {
+      options.drawPoints = {
+          onRender: options.drawPoints
+      };
+    }
+    
     if ('hiddenDates' in this.options) {
       DateUtil.convertHiddenOptions(this.body, this.options.hiddenDates);
     }

lib/timeline/component/GraphGroup.js

@@ -69,6 +69,13 @@ GraphGroup.prototype.setOptions = function(options) {
     var fields = ['sampling','style','sort','yAxisOrientation','barChart'];
     util.selectiveDeepExtend(fields, this.options, options);
 
+    // if the group's drawPoints is a function delegate the callback to the onRender property
+    if (typeof options.drawPoints == 'function') {
+  	  options.drawPoints = {
+  			  onRender: options.drawPoints
+  	  }
+    }
+    
     util.mergeOptions(this.options, options,'interpolation');
     util.mergeOptions(this.options, options,'drawPoints');
     util.mergeOptions(this.options, options,'shaded');