code: func (c *Overlay) HighlightQuad(quad []float64, color *DOMRGBA, outlineColor *DOMRGBA) (*gcdmessage.ChromeResponse, error) {
  	var v OverlayHighlightQuadParams
  	v.Quad = quad
  	v.Color = color
  	v.OutlineColor = outlineColor
  	return c.HighlightQuadWithParams(&v)
  }
docs: // HighlightQuad - Highlights given quad. Coordinates are absolute with respect to the main frame viewport.
  // quad - Quad to highlight
  // color - The highlight fill color (default: transparent).
  // outlineColor - The highlight outline color (default: transparent).