React v15: log and time stamp end of batch update

foo.patch

diff --git a/node_modules/react-dom/lib/ReactDefaultBatchingStrategy.js b/node_modules/react-dom/lib/ReactDefaultBatchingStrategy.js
index 5e149f0..96e34a0 100644
--- a/node_modules/react-dom/lib/ReactDefaultBatchingStrategy.js
+++ b/node_modules/react-dom/lib/ReactDefaultBatchingStrategy.js
@@ -20,6 +20,8 @@ var emptyFunction = require('fbjs/lib/emptyFunction');
 var RESET_BATCHED_UPDATES = {
   initialize: emptyFunction,
   close: function () {
+    console.timeStamp('end React batch update');
+    console.log('end React batch update');
     ReactDefaultBatchingStrategy.isBatchingUpdates = false;
   }
 };