**Do you want to request a _feature_ or report a _bug_?**
Bug
**What is the current behavior?**
React at the beginning rounds `input[type=range]` value to 0 or 1, and then looks at step parameter which is 0.1 for example. The result is incorrect value of input after component mounts. When I put `value` attribute after `step` attributes, it works fine.
**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/).**
Demo: https://jsfiddle.net/2Lm4gy5k/ Comment or uncomment line 13 and 14 to see the difference.

**What is the expected behavior?**
To always look at step parameter and then round the value (if required).
**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**
v15.1.0 (Opera, Chrome, Firefox). 

Yes, works in v.0.14.0 (https://jsfiddle.net/wrcnLugd/)

/**
 * 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.
 *
 * @emails react-core
 */
'use strict';
var emptyFunction = require('emptyFunction');
describe('ReactDOMInput', function() {
  var EventConstants;
  var React;
  var ReactDOM;
  var ReactDOMServer;
  var ReactDOMFeatureFlags;
  var ReactLink;
  var ReactTestUtils;
  var inputValueTracking;
  function setUntrackedValue(elem, value) {