code: func (c *Cast) StopCasting(sinkName string) (*gcdmessage.ChromeResponse, error) {
  	var v CastStopCastingParams
  	v.SinkName = sinkName
  	return c.StopCastingWithParams(&v)
  }
docs: // StopCasting - Stops the active Cast session on the sink.
  // sinkName -