Use a direct include of strings headers in cloud_print/.

cloud_print/common/win/cloud_print_utils.h

 // Copyright 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.
 
 #ifndef CLOUD_PRINT_COMMON_CLOUD_PRINT_UTILS_H_
 #define CLOUD_PRINT_COMMON_CLOUD_PRINT_UTILS_H_
 
 #include <wtypes.h>
 
-#include "base/string16.h"
+#include "base/strings/string16.h"
 
 namespace cloud_print {
 
 // Similar to the Windows API call GetLastError but returns an HRESULT.
 HRESULT GetLastHResult();
 
 // Convert an HRESULT to a localized string.
 string16 GetErrorMessage(HRESULT hr);
 
 // Retrieves a string from the string table of the module that contains the
 // calling code.
 string16 LoadLocalString(DWORD id);
 
 // Sets registry value to notify Google Update that product was used.
 void SetGoogleUpdateUsage(const string16& product_id);
 
 }  // namespace cloud_print
 
 #endif  // CLOUD_PRINT_COMMON_CLOUD_PRINT_UTILS_H_