React 0.14.7: `<option value="">empty</option>` emits empty string on change
http://jsbin.com/pisita/10/edit?html,js,console,output
React 15.0.0-rc.1`<option value="">empty</option>` emits string with value "empty" on change
http://jsbin.com/bemaze/12/edit?html,js,console,output
This is because React 15.0.0-rc.1 cuts off `value=""` from option tag

inputValueTracking.track(this);
}
function trapBubbledEventsLocal() {
  var inst = this;
  
  
  invariant(inst._rootNodeID, 'Must be mounted to trap events');
  var node = getNode(inst);
  invariant(
    node,
    'trapBubbledEvent(...): Requires node to be rendered.'
  );
  switch (inst._tag) {
    case 'iframe':
    case 'object':
      inst._wrapperState.listeners = [
        ReactBrowserEventEmitter.trapBubbledEvent(
          EventConstants.topLevelTypes.topLoad,
          'load',
          node
        ),