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 listenerToPut = this;
  EventPluginHub.putListener(
    listenerToPut.inst,
    listenerToPut.registrationName,
    listenerToPut.listener
  );
}
function inputPostMount() {
  var inst = this;
  ReactDOMInput.postMountWrapper(inst);
}
function textareaPostMount() {
  var inst = this;
  ReactDOMTextarea.postMountWrapper(inst);
}
function optionPostMount() {