**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`
}
      return false;
    }
  },
  
  
  unstable_createPortal: createPortal,
  unstable_batchedUpdates: ReactGenericBatching.batchedUpdates,
  unstable_deferredUpdates: DOMRenderer.deferredUpdates,
  flushSync: DOMRenderer.flushSync,
  __SECRET_INTERNALS_DO_NOT_USE_OR_YOU_WILL_BE_FIRED: {
    
    EventPluginHub: require('EventPluginHub'),
    
    EventPluginRegistry: require('EventPluginRegistry'),
    EventPropagators: require('EventPropagators'),
    ReactControlledComponent,
    ReactDOMComponentTree,
    ReactDOMEventListener: require('ReactDOMEventListener'),
  },
};
const foundDevTools = injectInternals({
  findFiberByHostInstance: ReactDOMComponentTree.getClosestInstanceFromNode,
  findHostInstanceByFiber: DOMRenderer.findHostInstance,
  
  bundleType: __DEV__ ? 1 : 0,
  version: ReactVersion,
  rendererPackageName: 'react-dom',
});
if (__DEV__) {