React 0.14.7: `<option value="">empty</option>` emits empty string on change
http://jsbin.com/pisita/10/edit?html,js,console,output
React 15.0.0-rc.1`<option value="">empty</option>` emits string with value "empty" on change
http://jsbin.com/bemaze/12/edit?html,js,console,output
This is because React 15.0.0-rc.1 cuts off `value=""` from option tag

/**
 * Copyright 2013-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD-style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 *
 * @providesModule ReactDOMInput
 */
'use strict';
var DisabledInputUtils = require('DisabledInputUtils');
var DOMPropertyOperations = require('DOMPropertyOperations');
var LinkedValueUtils = require('LinkedValueUtils');
var ReactDOMComponentTree = require('ReactDOMComponentTree');
var ReactUpdates = require('ReactUpdates');
var invariant = require('invariant');
var warning = require('warning');
var didWarnValueLink = false;
var didWarnCheckedLink = false;
var didWarnValueNull = false;
var didWarnValueDefaultValue = false;
var didWarnCheckedDefaultChecked = false;
var didWarnControlledToUncontrolled = false;
var didWarnUncontrolledToControlled = false;
function forceUpdateIfMounted() {