Use ScopedTaskEnvironment instead of MessageLoopForUI in chromeos tests.

chromeos/network/network_sms_handler_unittest.cc

Index: chromeos/network/network_sms_handler_unittest.cc
diff --git a/chromeos/network/network_sms_handler_unittest.cc b/chromeos/network/network_sms_handler_unittest.cc
index 77894c4faea053a2a5e3e54d5abf81102b92729c..f1e09e95cffcb23618505b301ec97aa14355a7d4 100644
--- a/chromeos/network/network_sms_handler_unittest.cc
+++ b/chromeos/network/network_sms_handler_unittest.cc
@@ -9,8 +9,8 @@
 #include <string>
 
 #include "base/command_line.h"
-#include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
+#include "base/test/scoped_task_environment.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/shill_device_client.h"
@@ -51,7 +51,9 @@ class TestObserver : public NetworkSmsHandler::Observer {
 
 class NetworkSmsHandlerTest : public testing::Test {
  public:
-  NetworkSmsHandlerTest() {}
+  NetworkSmsHandlerTest()
+      : scoped_task_environment_(
+            base::test::ScopedTaskEnvironment::MainThreadType::UI) {}
   ~NetworkSmsHandlerTest() override {}
 
   void SetUp() override {
@@ -88,7 +90,7 @@ class NetworkSmsHandlerTest : public testing::Test {
   }
 
  protected:
-  base::MessageLoopForUI message_loop_;
+  base::test::ScopedTaskEnvironment scoped_task_environment_;
   std::unique_ptr<NetworkSmsHandler> network_sms_handler_;
   std::unique_ptr<TestObserver> test_observer_;
 };