fix: do not fail if removing constraint fails

Author: td-famedly

lib/src/mediadevices_impl.dart

@@ -13,9 +13,14 @@ class MediaDevicesWeb extends MediaDevices {
       Map<String, dynamic> mediaConstraints) async {
     try {
       if (!isMobile) {
-        if (mediaConstraints['video'] is Map &&
-            mediaConstraints['video']['facingMode'] != null) {
-          mediaConstraints['video'].remove('facingMode');
+        try {
+          if (mediaConstraints['video'] is Map &&
+              mediaConstraints['video']['facingMode'] != null) {
+            mediaConstraints['video'].remove('facingMode');
+          }
+        } catch (e) {
+          print(
+              '[getUserMedia] failed to remove facingMode from mediaConstraints');
         }
       }