addClient abstract method
Must store client.
client must be returned by getClient after this method has been invoked, and until (if ever)
removeClient is invoked.
Implementation
FutureOr addClient(AuthServer server, AuthClient client);
Must store client.
client must be returned by getClient after this method has been invoked, and until (if ever)
removeClient is invoked.
FutureOr addClient(AuthServer server, AuthClient client);