Use a direct include of strings headers in chrome/browser/ui/webui/, part 1.

chrome/browser/ui/webui/help/version_updater_basic.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/webui/help/version_updater_basic.h"
 
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
 #include "chrome/browser/upgrade_detector.h"
 
 void VersionUpdaterBasic::CheckForUpdate(
     const StatusCallback& status_callback) {
   if (UpgradeDetector::GetInstance()->notify_upgrade())
     status_callback.Run(NEARLY_UPDATED, 0, string16());
   else
     status_callback.Run(DISABLED, 0, string16());
 }
 
 void VersionUpdaterBasic::RelaunchBrowser() const {
   chrome::AttemptRestart();
 }
 
 VersionUpdater* VersionUpdater::Create() {
   return new VersionUpdaterBasic;
 }