**Do you want to request a *feature* or report a *bug*?**
Bug

**What is the current behavior?**
I've started recieving this warning about my SVGs which is using [feGaussianBlur](https://developer.mozilla.org/en-US/docs/Web/SVG/Element/feGaussianBlur): 
`Warning: Expected server HTML to contain a matching <feGaussianBlur> in <filter>.`

**What is the expected behavior?**
Should be no warnings because there are no difference.

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**
Such behavior started right after updating to `React 16.0.0-rc.3` and never happened with `React 15.6.1`
<select value={['bar', 'baz']} multiple={true} readOnly={true}>
              {options}
            </select>,
          );
          expectSelectValue(e, ['bar', 'baz']);
        },
      );
      itRenders(
        'a select with a value and no onChange/readOnly',
        async render => {
          
          
          const e = await render(<select value="bar">{options}</select>, 1);
          expectSelectValue(e, 'bar');
        },
      );
      itRenders('a select with a defaultValue', async render => {
        const e = await render(<select defaultValue="bar">{options}</select>);
        expectSelectValue(e, 'bar');
      });
      itRenders('a select value overriding defaultValue', async render => {
        const e = await render(
          <select value="bar" defaultValue="baz" readOnly={true}>
            {options}
          </select>,
          1,
        );
        expectSelectValue(e, 'bar');
      });
      itRenders(