[whatwg] HTMLCanvasElement.toFile()

[João Eiras]

>> This function takes the same arguments as toDataURL(), plus an
>> additional 'name' argument. It produces the same result as
>> toDataURL(), except that it returns the result as a File object rather
>> than as a data-url encoded string. This can then be directly sent
>> using XMLHttpRequest.
>
> I think it would make more sense to have an actual type for binary data  
> (for example along the lines of my proposal on public-script-coord and  
> es-discuss) and enable getting one from <canvas> and sending via XHR.

How about just overloading xhr.send() to handle a <canvas> element ?