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

chrome/browser/chromeos/login/screens/error_screen.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/chromeos/login/screens/error_screen.h"
 
 #include "base/command_line.h"
 #include "chrome/browser/chromeos/login/auth/chrome_login_performer.h"
 #include "chrome/browser/chromeos/login/chrome_restart_request.h"
 #include "chrome/browser/chromeos/login/screens/error_screen_actor.h"
@@ skipping 56 matching lines @@
   NOTREACHED() << "Guest login failed.";
   guest_login_performer_.reset();
 }
 
 void ErrorScreen::OnAuthSuccess(const UserContext& user_context) {
   LOG(FATAL);
 }
 
 void ErrorScreen::OnOffTheRecordAuthSuccess() {
   // Restart Chrome to enter the guest session.
-  const CommandLine& browser_command_line = *CommandLine::ForCurrentProcess();
-  CommandLine command_line(browser_command_line.GetProgram());
+  const base::CommandLine& browser_command_line =
+      *base::CommandLine::ForCurrentProcess();
+  base::CommandLine command_line(browser_command_line.GetProgram());
   std::string cmd_line_str =
       GetOffTheRecordCommandLine(GURL(),
                                  StartupUtils::IsOobeCompleted(),
                                  browser_command_line,
                                  &command_line);
 
   RestartChrome(cmd_line_str);
 }
 
 void ErrorScreen::OnPasswordChangeDetected() {
@@ skipping 86 matching lines @@
   }
 
   if (guest_login_performer_)
     return;
 
   guest_login_performer_.reset(new ChromeLoginPerformer(this));
   guest_login_performer_->LoginOffTheRecord();
 }
 
 }  // namespace chromeos