Remove remaining calls to deprecated MessageLoop methods.

remoting/protocol/negotiating_authenticator_unittest.cc

Index: remoting/protocol/negotiating_authenticator_unittest.cc
diff --git a/remoting/protocol/negotiating_authenticator_unittest.cc b/remoting/protocol/negotiating_authenticator_unittest.cc
index a83e80b8c387c970b9cb0480a5d650d8bcbc4d8f..3e120323be1468af9da4783dcdf694bbe8a2b3a2 100644
--- a/remoting/protocol/negotiating_authenticator_unittest.cc
+++ b/remoting/protocol/negotiating_authenticator_unittest.cc
@@ -5,6 +5,7 @@
 #include "base/bind.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
+#include "base/run_loop.h"
 #include "net/base/net_errors.h"
 #include "remoting/base/rsa_key_pair.h"
 #include "remoting/protocol/auth_util.h"
@@ -141,7 +142,7 @@ class NegotiatingAuthenticatorTest : public AuthenticatorTestBase {
                                   kMessageSize, kMessages);
 
     tester.Start();
-    message_loop_.Run();
+    base::RunLoop().Run();
     tester.CheckResults();
   }