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

base/json/json_value_converter_unittest.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 "base/json/json_value_converter.h"
 
 #include <string>
 #include <vector>
 
 #include "base/json/json_reader.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
-#include "base/string_piece.h"
+#include "base/strings/string_piece.h"
 #include "base/values.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace base {
 namespace {
 
 // Very simple messages.
 struct SimpleMessage {
   enum SimpleEnum {
     FOO, BAR,
@@ skipping 223 matching lines @@
       "}\n";
 
   scoped_ptr<Value> value(base::JSONReader::Read(normal_data));
   SimpleMessage message;
   base::JSONValueConverter<SimpleMessage> converter;
   EXPECT_FALSE(converter.Convert(*value.get(), &message));
   // No check the values as mentioned above.
 }
 
 }  // namespace base