chromeos: Introduce ash::SystemTrayTestApi

chrome/browser/ui/ash/system_tray_delegate_chromeos_browsertest_chromeos.cc

Index: chrome/browser/ui/ash/system_tray_delegate_chromeos_browsertest_chromeos.cc
diff --git a/chrome/browser/ui/ash/system_tray_delegate_chromeos_browsertest_chromeos.cc b/chrome/browser/ui/ash/system_tray_delegate_chromeos_browsertest_chromeos.cc
index c0bcb28a5f753da685e780598b670dbee6fa3d8e..e4b2bf66829ab53f845b7e9169c9be252e6080a7 100644
--- a/chrome/browser/ui/ash/system_tray_delegate_chromeos_browsertest_chromeos.cc
+++ b/chrome/browser/ui/ash/system_tray_delegate_chromeos_browsertest_chromeos.cc
@@ -11,6 +11,7 @@
 #include "ash/system/date/system_info_default_view.h"
 #include "ash/system/date/tray_system_info.h"
 #include "ash/system/tray/system_tray.h"
+#include "ash/system/tray/system_tray_test_api.h"
 #include "base/macros.h"
 #include "chrome/browser/chromeos/login/login_manager_test.h"
 #include "chrome/browser/chromeos/login/session/user_session_manager.h"
@@ -34,19 +35,19 @@ namespace {
 const char kUser1[] = "user1@gmail.com";
 const char kUser2[] = "user2@gmail.com";
 
+ash::TraySystemInfo* GetTraySystemInfo() {
+  return ash::SystemTrayTestApi(ash::Shell::Get()->GetPrimarySystemTray())
+      .tray_system_info();
+}
+
 base::HourClockType GetHourType() {
-  const ash::TraySystemInfo* tray_system_info =
-      ash::Shell::Get()->GetPrimarySystemTray()->GetTraySystemInfoForTesting();
   const ash::SystemInfoDefaultView* system_info_default_view =
-      tray_system_info->GetDefaultViewForTesting();
-
+      GetTraySystemInfo()->GetDefaultViewForTesting();
   return system_info_default_view->GetDateView()->GetHourTypeForTesting();
 }
 
 void CreateDefaultView() {
-  ash::TraySystemInfo* tray_system_info =
-      ash::Shell::Get()->GetPrimarySystemTray()->GetTraySystemInfoForTesting();
-  tray_system_info->CreateDefaultViewForTesting(
+  GetTraySystemInfo()->CreateDefaultViewForTesting(
       ash::LoginStatus::NOT_LOGGED_IN);
 }