Move ReadFileToString to the base namespace.

chrome/browser/chromeos/system/automatic_reboot_manager_unittest.cc

 // Copyright (c) 2013 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/system/automatic_reboot_manager.h"
 
 #include <string>
 #include <utility>
 
 #include "ash/shell.h"
@@ skipping 460 matching lines @@
 
   if (is_user_logged_in_ || expect_reboot)
     VerifyLoginScreenIdleTimerIsStopped();
   else
     VerifyLoginScreenIdleTimerIsRunning();
 }
 
 bool AutomaticRebootManagerBasicTest::ReadUpdateRebootNeededUptimeFromFile(
     base::TimeDelta* uptime) {
   std::string contents;
-  if (!file_util::ReadFileToString(update_reboot_needed_uptime_file_,
-                                   &contents)) {
+  if (!base::ReadFileToString(update_reboot_needed_uptime_file_, &contents)) {
     return false;
   }
   double seconds;
   if (!base::StringToDouble(contents.substr(0, contents.find(' ')), &seconds) ||
       seconds < 0.0) {
     return false;
   }
   *uptime = base::TimeDelta::FromMilliseconds(seconds * 1000.0);
   return true;
 }
@@ skipping 1560 matching lines @@
 INSTANTIATE_TEST_CASE_P(
     AutomaticRebootManagerTestInstance,
     AutomaticRebootManagerTest,
     ::testing::Values(
         AUTOMATIC_REBOOT_MANAGER_TEST_SCENARIO_LOGIN_SCREEN,
         AUTOMATIC_REBOOT_MANAGER_TEST_SCENARIO_KIOSK_APP_SESSION,
         AUTOMATIC_REBOOT_MANAGER_TEST_SCENARIO_NON_KIOSK_APP_SESSION));
 
 }  // namespace system
 }  // namespace chromeos