event.preventDefault in click handler does not prevent onChange from being called

**Do you want to request a *feature* or report a *bug*?** Bug! **What is the current behavior?** When rendering an `input` element of type `checkbox` with an `onClick` and `onChange` handler, `onChange` is still called even though `event.preventDefault()` is called in the `onClick` handler. **If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem via https://jsfiddle.net or similar (template: https://jsfiddle.net/reactjs/69z2wepo/).** http://jsfiddle.net/rf3w7apc/ **What is the expected behavior?** Calling `event.preventDefault` in the `onClick` handler should prevent the default action from occurring (or undo its effect), which is to update the value of the `input` element. This should stop any `change` event listener from being invoked. See https://jsfiddle.net/L1eskzsq/ for expected behavior **Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?** Tested using a build from master, macOS 10.12.2, verified in: * Chrome 56.0.2924.87 (64-bit) * Firefox 51.0.1 (64-bit) Safari 10.0.2 calls the `change` event listener in both cases.