code: func (c *Emulation) SetPageScaleFactor(pageScaleFactor float64) (*gcdmessage.ChromeResponse, error) {
  	var v EmulationSetPageScaleFactorParams
  	v.PageScaleFactor = pageScaleFactor
  	return c.SetPageScaleFactorWithParams(&v)
  }
docs: // SetPageScaleFactor - Sets a specified page scale factor.
  // pageScaleFactor - Page scale factor.