Remove first_message argument from AuthenticatorFactory::Create().

remoting/protocol/me2me_host_authenticator_factory.cc

Index: remoting/protocol/me2me_host_authenticator_factory.cc
diff --git a/remoting/protocol/me2me_host_authenticator_factory.cc b/remoting/protocol/me2me_host_authenticator_factory.cc
index 56e96317ac01bbc5b7f051be5fe358709cd7bcc9..1d8b5b08b6a815bc9337108213761ba00b66829b 100644
--- a/remoting/protocol/me2me_host_authenticator_factory.cc
+++ b/remoting/protocol/me2me_host_authenticator_factory.cc
@@ -62,16 +62,13 @@ Me2MeHostAuthenticatorFactory::CreateWithThirdPartyAuth(
   return std::move(result);
 }
 
-Me2MeHostAuthenticatorFactory::Me2MeHostAuthenticatorFactory() {
-}
+Me2MeHostAuthenticatorFactory::Me2MeHostAuthenticatorFactory() {}
 
-Me2MeHostAuthenticatorFactory::~Me2MeHostAuthenticatorFactory() {
-}
+Me2MeHostAuthenticatorFactory::~Me2MeHostAuthenticatorFactory() {}
 
 scoped_ptr<Authenticator> Me2MeHostAuthenticatorFactory::CreateAuthenticator(
     const std::string& local_jid,
-    const std::string& remote_jid,
-    const buzz::XmlElement* first_message) {
+    const std::string& remote_jid) {
 
   std::string remote_jid_prefix;