Replace direct access to kGoogleServicesUsername with calls to SigninManager.

chrome/browser/ui/browser_navigator_browsertest_chromeos.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 "chrome/browser/ui/browser_navigator_browsertest.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "chrome/browser/chromeos/login/chrome_restart_request.h"
@@ skipping 139 matching lines @@
   return GURL("http://www.google.com/");
 }
 
 // Subclass that tests navigation while in the Guest session.
 class BrowserGuestSessionNavigatorTest: public BrowserNavigatorTest {
  protected:
   virtual void SetUpCommandLine(CommandLine* command_line) override {
     CommandLine command_line_copy = *command_line;
     command_line_copy.AppendSwitchASCII(
         chromeos::switches::kLoginProfile, "user");
+    command_line_copy.AppendSwitch(chromeos::switches::kGuestSession);
     chromeos::GetOffTheRecordCommandLine(GetGoogleURL(),
                                          true,
                                          command_line_copy,
                                          command_line);
   }
 };
 
 // This test verifies that the settings page is opened in the incognito window
 // in Guest Session (as well as all other windows in Guest session).
 IN_PROC_BROWSER_TEST_F(BrowserGuestSessionNavigatorTest,
@@ skipping 69 matching lines @@
 
     EXPECT_EQ(3u, chrome::GetTotalBrowserCount());
 
     // The ShowWindowForUser should not have been called since the window is
     // already on the correct desktop.
     ASSERT_FALSE(manager->created_window());
   }
 }
 
 }  // namespace