Thx. I would like to trigger a "onchange" event like this:
```js 
this.emit("change", {percent: percent});
```
It works fine and allow things like:
```html
<d-progress-bar onchange="alert(event.percent + '/' + this.value)';"></d-progress-bar>
```
The thing is, if I define a  `onchange()` function it breaks something with an error `TypeError: 'onchange' setter called on an object that does not implement interface HTMLElement`.

Did I miss something?