code: function distanceToFurthestCorner(x, y, rect) {
      var /** @type {?} */ distX = Math.max(Math.abs(x - rect.left), Math.abs(x - rect.right));
      var /** @type {?} */ distY = Math.max(Math.abs(y - rect.top), Math.abs(y - rect.bottom));
      return Math.sqrt(distX * distX + distY * distY);
  }
docs: Returns the distance from the point (x, y) to the furthest corner of a rectangle.
  @param {?} x
  @param {?} y
  @param {?} rect
  @return {?}