The error event on `<source>` elements doesn't work. Looking at #4370, it seems like there is an `onError` for `<video>` but I can't tell if that's supposed to work for `<source>` too.

The error event is useful so I can deduce which format the browser is using.

var ReactDOMOption = require('ReactDOMOption');
var ReactDOMSelect = require('ReactDOMSelect');
var ReactDOMTextarea = require('ReactDOMTextarea');
var ReactInstrumentation = require('ReactInstrumentation');
var ReactMultiChild = require('ReactMultiChild');
var ReactServerRenderingTransaction = require('ReactServerRenderingTransaction');
var emptyFunction = require('emptyFunction');
var escapeTextContentForBrowser = require('escapeTextContentForBrowser');
var invariant = require('invariant');
var isEventSupported = require('isEventSupported');
var keyOf = require('keyOf');
var shallowEqual = require('shallowEqual');
var inputValueTracking = require('inputValueTracking');
var validateDOMNesting = require('validateDOMNesting');
var warning = require('warning');
var Flags = ReactDOMComponentFlags;
var deleteListener = EventPluginHub.deleteListener;
var getNode = ReactDOMComponentTree.getNodeFromInstance;
var listenTo = ReactBrowserEventEmitter.listenTo;
var registrationNameModules = EventPluginRegistry.registrationNameModules;
var CONTENT_TYPES = {'string': true, 'number': true};
var STYLE = keyOf({style: null});
var HTML = keyOf({__html: null});
var RESERVED_PROPS = {
  children: null,
  dangerouslySetInnerHTML: null,
  suppressContentEditableWarning: null,
};
var DOC_FRAGMENT_TYPE = 11;
function getDeclarationErrorAddendum(internalInstance) {