src/vs/base/browser/dom.ts/getDomNodePagePosition
export function getDomNodePagePosition(domNode: HTMLElement): IDomNodePagePosition {
	let bb = domNode.getBoundingClientRect();
	return {
		left: bb.left + StandardWindow.scrollX,
		top: bb.top + StandardWindow.scrollY,
		width: bb.width,
		height: bb.height
	};
}