Fix mobile qr code scan support

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

@@ -61,7 +61,6 @@ export class QrCodeScanner extends ScopedElementsMixin(DBPLitElement) {
             let devices_map = new Map();
 
             const that = this;
-            let counter = 0;
 
             if (navigator.mediaDevices
                 && navigator.mediaDevices.enumerateDevices
@@ -75,12 +74,8 @@ export class QrCodeScanner extends ScopedElementsMixin(DBPLitElement) {
                             if (device.kind === 'videoinput') {
                                 let id = device.deviceId;
                                 if (/Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent)) {
-                                    if (counter === 0) {
-                                        devices_map.set('environment', i18n.t('back-camera'));
-                                        counter = 1;
-                                    } else {
-                                        devices_map.set('user', i18n.t('front-camera'));
-                                    }
+                                    devices_map.set('environment', i18n.t('back-camera'));
+                                    devices_map.set('user', i18n.t('front-camera'));
                                 } else {
                                     devices_map.set(id ? id : true, device.label || i18n.t('camera') + (devices_map.size + 1));
                                 }
@@ -166,10 +161,15 @@ export class QrCodeScanner extends ScopedElementsMixin(DBPLitElement) {
         const that = this;
         let constraint = { video:  { deviceId: this._('#videoSource').options[this._('#videoSource').selectedIndex].value } };
 
-        if ( (this._('#videoSource').options[this._('#videoSource').selectedIndex].value === 'environment') || (this._('#videoSource').options[this._('#videoSource').selectedIndex].value === 'user') ) {
+        if ( (this._('#videoSource').options[this._('#videoSource').selectedIndex].value === 'environment') ) {
             constraint =  { video: { facingMode: "environment" } };
+        } else if ( this._('#videoSource').options[this._('#videoSource').selectedIndex].value === 'user' ) {
+            constraint =  { video: { facingMode: "user" } };
         }
-        that._("#error").innerText += " constraint: " + JSON.stringify(constraint);
+
+
+
+
 
         navigator.mediaDevices.getUserMedia(constraint).then(function(stream) {
             video.srcObject = stream;