Rewrite base::JSONReader to be 35-40% faster, depending on the input string.

base/values.cc

 // Copyright (c) 2011 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/values.h"
 
 #include <algorithm>
 
 #include "base/float_util.h"
 #include "base/logging.h"
@@ skipping 676 matching lines @@
               static_cast<const DictionaryValue*>(merge_value));
           continue;
         }
       }
       // All other cases: Make a copy and hook it up.
       SetWithoutPathExpansion(*key, merge_value->DeepCopy());
     }
   }
 }
 
+void DictionaryValue::Swap(DictionaryValue* other) {
+  dictionary_.swap(other->dictionary_);
+}
+
 DictionaryValue* DictionaryValue::DeepCopy() const {
   DictionaryValue* result = new DictionaryValue;
 
   for (ValueMap::const_iterator current_entry(dictionary_.begin());
        current_entry != dictionary_.end(); ++current_entry) {
     result->SetWithoutPathExpansion(current_entry->first,
                                     current_entry->second->DeepCopy());
   }
 
   return result;
@@ skipping 194 matching lines @@
     return false;
 
   list_.insert(list_.begin() + index, in_value);
   return true;
 }
 
 ListValue::const_iterator ListValue::Find(const Value& value) const {
   return std::find_if(list_.begin(), list_.end(), ValueEquals(&value));
 }
 
+void ListValue::Swap(ListValue* other) {
+  list_.swap(other->list_);
+}
+
 bool ListValue::GetAsList(ListValue** out_value) {
   if (out_value)
     *out_value = this;
   return true;
 }
 
 bool ListValue::GetAsList(const ListValue** out_value) const {
   if (out_value)
     *out_value = this;
   return true;
@@ skipping 24 matching lines @@
   if (lhs_it != end() || rhs_it != other_list->end())
     return false;
 
   return true;
 }
 
 ValueSerializer::~ValueSerializer() {
 }
 
 }  // namespace base