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

chrome/browser/ui/webui/help/version_updater.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_HELP_VERSION_UPDATER_H_
 #define CHROME_BROWSER_UI_WEBUI_HELP_VERSION_UPDATER_H_
 
 #include <string>
 
 #include "base/callback.h"
-#include "base/string16.h"
+#include "base/strings/string16.h"
 
 // Interface implemented to expose per-platform updating functionality.
 class VersionUpdater {
  public:
   // Update process state machine.
   enum Status {
     CHECKING,
     UPDATING,
     NEARLY_UPDATED,
     UPDATED,
@@ skipping 52 matching lines @@
   // Relaunches the browser, generally after being updated.
   virtual void RelaunchBrowser() const = 0;
 
 #if defined(OS_CHROMEOS)
   virtual void SetReleaseChannel(const std::string& channel) = 0;
   virtual void GetReleaseChannel(const ChannelCallback& callback) = 0;
 #endif
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_HELP_VERSION_UPDATER_H_