webrtc aspect

//メンバ変数を用意する
var videoFrame: CGRect? = nil  



    //向きを伝える
    override func viewDidAppear(_ animated: Bool) {
        
        NotificationCenter.default.addObserver(self, selector: #selector(ChatViewController.onOrientationChange(notification:)), name: NSNotification.Name.UIDeviceOrientationDidChange, object: nil)
    }
    
    //縦向きに戻った時にまたアスペクト比をを揃える
    func onOrientationChange(notification: NSNotification){
        let deviceOrientation: UIDeviceOrientation!  = UIDevice.current.orientation
        if videoFrame != nil {
            if UIDeviceOrientationIsPortrait(deviceOrientation){
                remoteVideoView.frame = videoFrame!
            }
        }
    }

    //videoViewのフレームサイズをメンバ変数へ
    func videoView(_ videoView: RTCEAGLVideoView, didChangeVideoSize size: CGSize) {
        let width = self.view.frame.width
        let height =
            self.view.frame.width * size.height / size.width
        videoView.frame = CGRect(
            x: 0,
            y: (self.view.frame.height - height) / 2,
            width: width,
            height: height)
        videoFrame = videoView.frame
    }