Clean code

packages/qr-code-scanner/src/qr-code-scanner.js

@@ -92,9 +92,6 @@ async function createVideoElement(deviceId) {
     if (stream !== null) {
         let video = document.createElement("video");
         video.srcObject = stream;
-        video.setAttribute('autoplay', '');
-        video.setAttribute('muted', '');
-        video.setAttribute('playsinline', '');
         return video;
     }
 
@@ -335,9 +332,7 @@ export class QrCodeScanner extends ScopedElementsMixin(DBPLitElement) {
 
         if (video !== null) {
             video.setAttribute("playsinline", true); // required to tell iOS safari we don't want fullscreen
-            video.onloadedmetadata = function(e){
-                video.play();
-            };
+            video.play();
             this._videoRunning = true;
 
             console.assert(this._requestID === null);