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

chrome/browser/automation/testing_automation_provider.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 "chrome/browser/automation/testing_automation_provider.h"
 
 #include <map>
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 2110 matching lines @@
         BlockedContentTabHelper* blocked_content =
             tab_contents->blocked_content_tab_helper();
         *count = static_cast<int>(blocked_content->GetBlockedContentsCount());
       }
   }
 }
 
 void TestingAutomationProvider::SendJSONRequest(int handle,
                                                 const std::string& json_request,
                                                 IPC::Message* reply_message) {
-  scoped_ptr<Value> values;
-  base::JSONReader reader;
   std::string error;
-  values.reset(reader.ReadAndReturnError(json_request,
+  scoped_ptr<Value> values(base::JSONReader::ReadAndReturnError(json_request,
       base::JSON_ALLOW_TRAILING_COMMAS, NULL, &error));
   if (!error.empty()) {
     AutomationJSONReply(this, reply_message).SendError(error);
     return;
   }
 
   // Make sure input is a dict with a string command.
   std::string command;
   DictionaryValue* dict_value = NULL;
   if (values->GetType() != Value::TYPE_DICTIONARY) {
@@ skipping 4969 matching lines @@
       *browser_handle = browser_tracker_->Add(browser);
       *success = true;
     }
   }
 }
 
 void TestingAutomationProvider::OnRemoveProvider() {
   if (g_browser_process)
     g_browser_process->GetAutomationProviderList()->RemoveProvider(this);
 }