Use a direct include of strings headers in chrome/browser/chromeos/.

chrome/browser/chromeos/system/ash_system_tray_delegate.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/system/ash_system_tray_delegate.h"
 
 #include <algorithm>
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 23 matching lines @@
 #include "ash/system/user/user_observer.h"
 #include "ash/volume_control_delegate.h"
 #include "ash/wm/lock_state_controller.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
 #include "base/chromeos/chromeos_version.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/memory/weak_ptr.h"
 #include "base/prefs/pref_service.h"
-#include "base/stringprintf.h"
+#include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/time.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/accessibility/accessibility_manager.h"
 #include "chrome/browser/chromeos/accessibility/magnification_manager.h"
 #include "chrome/browser/chromeos/audio/audio_handler.h"
 #include "chrome/browser/chromeos/bluetooth/bluetooth_pairing_dialog.h"
 #include "chrome/browser/chromeos/choose_mobile_network_dialog.h"
 #include "chrome/browser/chromeos/cros/cros_library.h"
 #include "chrome/browser/chromeos/cros/network_library.h"
@@ skipping 1291 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(SystemTrayDelegate);
 };
 
 }  // namespace
 
 ash::SystemTrayDelegate* CreateSystemTrayDelegate() {
   return new chromeos::SystemTrayDelegate();
 }
 
 }  // namespace chromeos