• Made the click behavior for radio buttons and checkboxes work when doing el.dispatchEvent(clickEvent), not just when doing el.click(). (@brandon-bethke-neudesic)
• Added defaultPrevented property to Event instances, reflecting whether ev.preventDefault() has been called. (@brandon-bethke-neudesic)
• Moved the click() method from HTMLInputElement.prototype to HTMLElement.prototype, per the latest spec.
• Made the click() method trigger a MouseEvent instead of just an Event.