[whatwg] Make the files attribute of the input element writable

[Boris Zbarsky]

On 12/15/12 8:39 PM, Jonas Sicking wrote:
> myFileInput.files = [ablob, afile, anotherblob, new Blob(["foo"])];

There's no way to express that in WebIDL, but I think that's a bug we 
should fix in WebIDL.  We should allow getters and setters for 
attributes to accept different IDL types...

-Boris