Correct const accessors in base/values.(h|cc), Part II (ListValue)

base/json/json_writer.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_writer.h"
 
 #include <cmath>
 
 #include "base/json/string_escape.h"
 #include "base/logging.h"
@@ skipping 121 matching lines @@
       }
 
     case Value::TYPE_LIST:
       {
         json_string_->append("[");
         if (pretty_print_)
           json_string_->append(" ");
 
         const ListValue* list = static_cast<const ListValue*>(node);
         for (size_t i = 0; i < list->GetSize(); ++i) {
-          Value* value = NULL;
+          const Value* value = NULL;
           bool result = list->Get(i, &value);
           DCHECK(result);
 
           if (omit_binary_values_ && value->GetType() == Value::TYPE_BINARY) {
             continue;
           }
 
           if (i != 0) {
             json_string_->append(",");
             if (pretty_print_)
@@ skipping 74 matching lines @@
   JsonDoubleQuote(UTF8ToUTF16(str), true, json_string_);
 }
 
 void JSONWriter::IndentLine(int depth) {
   // It may be faster to keep an indent string so we don't have to keep
   // reallocating.
   json_string_->append(std::string(depth * 3, ' '));
 }
 
 }  // namespace base