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.

];
      break;
    case 'video':
    case 'audio':
      inst._wrapperState.listeners = [];
      
      for (var event in mediaEvents) {
        if (mediaEvents.hasOwnProperty(event)) {
          inst._wrapperState.listeners.push(
            ReactBrowserEventEmitter.trapBubbledEvent(
              EventConstants.topLevelTypes[event],
              mediaEvents[event],
              node
            )
          );
        }
      }
      break;
    case 'img':
      inst._wrapperState.listeners = [
        ReactBrowserEventEmitter.trapBubbledEvent(
          EventConstants.topLevelTypes.topError,
          'error',
          node
        ),
        ReactBrowserEventEmitter.trapBubbledEvent(
          EventConstants.topLevelTypes.topLoad,
          'load',
          node
        ),