Add note about onScroll in 17

Author: gaearon

content/docs/reference-events.md

@@ -354,6 +354,10 @@ Event names:
 onScroll
 ```
 
+>Note
+>
+>Starting with React 17, the `onScroll` event **does not bubble** in React. This matches the browser behavior and prevents the confusion when a nested scrollable element fires events on a distant parent.
+
 Properties:
 
 ```javascript