Use ScopedTaskEnvironment instead of MessageLoopForUI in chromeos tests.

chromeos/network/prohibited_technologies_handler_unittest.cc

 // Copyright 2015 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/network/prohibited_technologies_handler.h"
 
 #include <memory>
 #include <string>
 #include <utility>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/json/json_reader.h"
 #include "base/macros.h"
-#include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
+#include "base/test/scoped_task_environment.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/network/managed_network_configuration_handler_impl.h"
 #include "chromeos/network/network_configuration_handler.h"
 #include "chromeos/network/network_profile_handler.h"
 #include "chromeos/network/network_state_test.h"
 #include "chromeos/network/onc/onc_utils.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
 
 namespace chromeos {
 
 class ProhibitedTechnologiesHandlerTest : public NetworkStateTest {
  public:
-  ProhibitedTechnologiesHandlerTest() {}
+  ProhibitedTechnologiesHandlerTest()
+      : scoped_task_environment_(
+            base::test::ScopedTaskEnvironment::MainThreadType::UI) {}
 
   void SetUp() override {
     DBusThreadManager::Initialize();
     LoginState::Initialize();
 
     NetworkStateTest::SetUp();
 
     test_manager_client()->AddTechnology(shill::kTypeCellular,
                                          true /* enabled */);
 
@@ skipping 62 matching lines @@
     }
     base::RunLoop().RunUntilIdle();
   }
 
   std::unique_ptr<ProhibitedTechnologiesHandler>
       prohibited_technologies_handler_;
   std::unique_ptr<NetworkConfigurationHandler> network_config_handler_;
   std::unique_ptr<ManagedNetworkConfigurationHandlerImpl>
       managed_config_handler_;
   std::unique_ptr<NetworkProfileHandler> network_profile_handler_;
-  base::MessageLoopForUI message_loop_;
+  base::test::ScopedTaskEnvironment scoped_task_environment_;
   base::DictionaryValue global_config_disable_wifi;
   base::DictionaryValue global_config_disable_wifi_and_cell;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ProhibitedTechnologiesHandlerTest);
 };
 
 TEST_F(ProhibitedTechnologiesHandlerTest,
        ProhibitedTechnologiesAllowedLoginScreen) {
   EXPECT_TRUE(
@@ skipping 47 matching lines @@
   network_state_handler()->SetTechnologyEnabled(
       NetworkTypePattern::Cellular(), true, network_handler::ErrorCallback());
   base::RunLoop().RunUntilIdle();
   EXPECT_FALSE(
       network_state_handler()->IsTechnologyEnabled(NetworkTypePattern::WiFi()));
   EXPECT_TRUE(network_state_handler()->IsTechnologyEnabled(
       NetworkTypePattern::Cellular()));
 }
 
 }  // namespace chromeos