Make callers of CommandLine use it via the base:: namespace.

chrome/browser/chromeos/policy/device_system_use_24hour_clock_browsertest.cc

 // Copyright 2014 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 "ash/shell.h"
 #include "ash/system/date/date_default_view.h"
 #include "ash/system/date/date_view.h"
 #include "ash/system/user/login_status.h"
 #include "base/command_line.h"
 #include "base/message_loop/message_loop.h"
 #include "chrome/browser/chromeos/policy/device_policy_cros_browser_test.h"
 #include "chrome/browser/chromeos/policy/proto/chrome_device_policy.pb.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/ui/ash/system_tray_delegate_chromeos.h"
 #include "chromeos/chromeos_switches.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace em = enterprise_management;
 
 namespace chromeos {
 
 class SystemUse24HourClockPolicyTest
     : public policy::DevicePolicyCrosBrowserTest {
  public:
   SystemUse24HourClockPolicyTest() {
   }
 
-  virtual void SetUpCommandLine(CommandLine* command_line) override {
+  virtual void SetUpCommandLine(base::CommandLine* command_line) override {
     command_line->AppendSwitch(switches::kLoginManager);
     command_line->AppendSwitch(chromeos::switches::kForceLoginManagerInTests);
   }
 
   virtual void SetUpInProcessBrowserTestFixture() override {
     InstallOwnerKey();
     MarkAsEnterpriseOwned();
     DevicePolicyCrosBrowserTest::SetUpInProcessBrowserTestFixture();
   }
 
@@ skipping 112 matching lines @@
   EXPECT_TRUE(CrosSettings::Get()->GetBoolean(kSystemUse24HourClock,
                                               &system_use_24hour_clock));
   EXPECT_FALSE(system_use_24hour_clock);
   EXPECT_FALSE(GetSystemTrayDelegateShouldUse24HourClock());
   EXPECT_EQ(base::k12HourClock, TestGetPrimarySystemTrayTimeHourType());
   EXPECT_TRUE(TestPrimarySystemTrayHasDateDefaultView());
   EXPECT_EQ(base::k12HourClock, TestGetPrimarySystemTrayDateHourType());
 }
 
 }  // namespace chromeos