src/vs/base/browser/ui/widget.ts/Widget/onkeydown
class Widget:	protected onkeydown(domNode: HTMLElement, listener: (e: IKeyboardEvent) => void): void {
		this._register(dom.addDisposableListener(domNode, dom.EventType.KEY_DOWN, (e: KeyboardEvent) => listener(new StandardKeyboardEvent(e))));
	}