base: Update the include paths of base/string_piece.h to its new location.

base/json/json_reader.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.
 //
 // A JSON parser.  Converts strings of JSON into a Value object (see
 // base/values.h).
 // http://www.ietf.org/rfc/rfc4627.txt?number=4627
 //
 // Known limitations/deviations from the RFC:
 // - Only knows how to parse ints within the range of a signed 32 bit int and
@@ skipping 15 matching lines @@
 // TODO(tc): Add an option to disable comment stripping
 
 #ifndef BASE_JSON_JSON_READER_H_
 #define BASE_JSON_JSON_READER_H_
 
 #include <string>
 
 #include "base/base_export.h"
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/string_piece.h"
+#include "base/strings/string_piece.h"
 
 namespace base {
 class Value;
 
 namespace internal {
 class JSONParser;
 }
 }
 
 namespace base {
@@ skipping 79 matching lines @@
   // numbers if appropriate.
   std::string GetErrorMessage() const;
 
  private:
   scoped_ptr<internal::JSONParser> parser_;
 };
 
 }  // namespace base
 
 #endif  // BASE_JSON_JSON_READER_H_