From "[WHATWG HTML Living Standard]
(https://html.spec.whatwg.org/multipage/indices.html#event-load)", the definition of 'onload':
> Fired at the Window when the document has finished loading; fired at an
element containing a resource (e.g. img, embed) when its resource has finished
loading
To adhere to that specification both handlers should be called as many times as Image loads.
From Google Chrome's Developer Tools:
```js
> function handler(evt) { console.log('img handler: %s', evt.type); }
< undefined
> var img = document.createElement('img')
< undefined
> img.onload = handler
< handler(evt)
> img.onerror = handler
< handler(evt)
> img.src = 'https://www.google.com/images/errors/logo_sm_2.png'; true
< true
< img handler: load
> img.src = 'https://www.google.com/images/errors/logo_sm_2.png'; true
< true
< img handler: load
> img.src = 'https://example.com/404.png'; true
< true
< img handler: error
> img.src = 'https://example.com/404.png'; true
< true
< img handler: error
```
Linus Unnebäck
Raul Ochoa
kibao
William Riancho
Tj Holowaychuk
