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**Do you want to request a *feature* or report a *bug*?**
Bug? (not a biggy - not sure if IE11 is support for development)

**What is the current behavior?**

IE11 seems to always throw a warning for hydration failures
eg

> **Warning: Prop `style` did not match. Server: "text-decoration: none;" Client: "text-decoration:none"**

Note: there is a space between the colon and none from Server, Client has no space

**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 for React 16: https://jsfiddle.net/Luktwrdm/, template for React 15: https://jsfiddle.net/hmbg7e9w/).**

Have a SSR rendered component, using inline styles
```
                       <a href="/page1" style={{ textDecoration: "none" }}>
                            <h1 className="splash-head">Go to Page1</h1>
                        </a>
```

Then hydrate it on IE11
`ReactDOM.hydrate(component, document.getElementById("app"));`

This **doesnt** occur in either Chrome or Firefox

**What is the expected behavior?**

No warning

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**

React: 16.1.1
Browser: IE11


});
  
  it('should not focus on either server or client with autofocus={false} even if there is a markup mismatch', () => {
    const element = document.createElement('div');
    element.innerHTML = ReactDOMServer.renderToString(
      <button autoFocus={false}>server</button>,
    );
    expect(element.firstChild.autofocus).toBe(false);
    element.firstChild.focus = jest.fn();
    expect(() =>
      ReactDOM.hydrate(<button autoFocus={false}>client</button>, element),
    ).toWarnDev(
      'Warning: Text content did not match. Server: "server" Client: "client"',
      {withoutStack: true},
    );
    expect(element.firstChild.focus).not.toHaveBeenCalled();
  });
  it('should throw rendering portals on the server', () => {
    const div = document.createElement('div');
    expect(() => {
      ReactDOMServer.renderToString(
        <div>{ReactDOM.createPortal(<div />, div)}</div>,
      );
    }).toThrow(
      'Portals are not currently supported by the server renderer. ' +
        'Render them conditionally so that they only appear on the client render.',
    );
  });
  it('should be able to render and hydrate Mode components', () => {
    class ComponentWithWarning extends React.Component {