Merge pull request #2098 from w3c/issue-2066-usvstring-alt

Relax PublicKeyCredentialRequestOptions.rpId to DOMString

index.bs

@@ -3513,7 +3513,7 @@ an assertion. Its {{PublicKeyCredentialRequestOptions/challenge}} member MUST be
     dictionary PublicKeyCredentialRequestOptions {
         required BufferSource                challenge;
         unsigned long                        timeout;
-        USVString                            rpId;
+        DOMString                            rpId;
         sequence<PublicKeyCredentialDescriptor> allowCredentials = [];
         DOMString                            userVerification = "preferred";
         sequence<DOMString>                  hints = [];