Function includeScroll

app/src/static/js/react-bootstrap.js:3300–3310

(rect, element)

function includeScroll(rect, element) {
  var subtract = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : false;
  var scrollTop = getScroll(element, 'top');
  var scrollLeft = getScroll(element, 'left');
  var modifier = subtract ? -1 : 1;
  rect.top += scrollTop * modifier;
  rect.bottom += scrollTop * modifier;
  rect.left += scrollLeft * modifier;
  rect.right += scrollLeft * modifier;
  return rect;
}
/*
 * Helper to detect borders of a given element
 * @method