Make nesting/running states a RunLoop rather than a MessageLoop concept.

chromeos/dbus/services/service_provider_test_helper.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chromeos/dbus/services/service_provider_test_helper.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/run_loop.h"
@@ skipping 140 matching lines @@
 void ServiceProviderTestHelper::MockSendSignal(dbus::Signal* signal) {
   // Run the callback captured in MockConnectToSignal(). This will call
   // OnSignalReceived().
   on_signal_callback_.Run(signal);
 }
 
 void ServiceProviderTestHelper::OnResponse(
     std::unique_ptr<dbus::Response> response) {
   response_ = std::move(response);
   response_received_ = true;
-  if (base::MessageLoop::current()->is_running())
+  if (base::RunLoop::IsRunningOnCurrentThread())
     base::MessageLoop::current()->QuitWhenIdle();
 }
 
 }  // namespace chromeos