Add base:: to string16s in chrome/.

chrome/installer/util/google_chrome_binaries_distribution.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.
 //
 // This file declares a class that contains various method related to branding.
 
 #ifndef CHROME_INSTALLER_UTIL_GOOGLE_CHROME_BINARIES_DISTRIBUTION_H_
 #define CHROME_INSTALLER_UTIL_GOOGLE_CHROME_BINARIES_DISTRIBUTION_H_
 
 #include "chrome/installer/util/chromium_binaries_distribution.h"
 
 class GoogleChromeBinariesDistribution : public ChromiumBinariesDistribution {
  public:
-  virtual string16 GetAppGuid();
+  virtual base::string16 GetAppGuid();
 
-  virtual string16 GetDisplayName();
+  virtual base::string16 GetDisplayName();
 
-  virtual string16 GetShortcutName(ShortcutType shortcut_type);
+  virtual base::string16 GetShortcutName(ShortcutType shortcut_type);
 
-  virtual string16 GetStateKey();
+  virtual base::string16 GetStateKey();
 
-  virtual string16 GetStateMediumKey();
+  virtual base::string16 GetStateMediumKey();
 
-  virtual string16 GetVersionKey();
+  virtual base::string16 GetVersionKey();
 
   virtual void UpdateInstallStatus(bool system_install,
       installer::ArchiveType archive_type,
       installer::InstallStatus install_status);
 
  protected:
   friend class BrowserDistribution;
 
   GoogleChromeBinariesDistribution();
 
  private:
   DISALLOW_COPY_AND_ASSIGN(GoogleChromeBinariesDistribution);
 };
 
 #endif  // CHROME_INSTALLER_UTIL_GOOGLE_CHROME_BINARIES_DISTRIBUTION_H_