[whatwg] Drop event on form controls

[Olli Pettay]

Hi all,

seems like the draft doesn't specify properly what should happen when
dropping something to a (text) form control.

The draft says that if dragover isn't canceled, then drag operation 
becomes none, and then later "if the current drag operation is none... 
then the drag operation failed."

Seems like dragover needs to have some default handling when dispatched
to form controls.
IE does dispatch a drop event when dragging something to a form control.

br,

-Olli