Added support for multiple parameters to Extension API callbacks.

chrome/browser/extensions/extension_test_api.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/extensions/extension_test_api.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/memory/singleton.h"
@@ skipping 87 matching lines @@
   AddRef();  // balanced in Reply
   content::NotificationService::current()->Notify(
       chrome::NOTIFICATION_EXTENSION_TEST_MESSAGE,
       content::Source<ExtensionTestSendMessageFunction>(this),
       content::Details<std::string>(&message));
   return true;
 }
 ExtensionTestSendMessageFunction::~ExtensionTestSendMessageFunction() {}
 
 void ExtensionTestSendMessageFunction::Reply(const std::string& message) {
-  result_.reset(Value::CreateStringValue(message));
+  SetSingleResult(Value::CreateStringValue(message));
   SendResponse(true);
   Release();  // balanced in RunImpl
 }
 
 // static
 void ExtensionTestGetConfigFunction::set_test_config_state(
     DictionaryValue* value) {
   TestConfigState* test_config_state = TestConfigState::GetInstance();
   test_config_state->set_config_state(value);
 }
@@ skipping 10 matching lines @@
 ExtensionTestGetConfigFunction::~ExtensionTestGetConfigFunction() {}
 
 bool ExtensionTestGetConfigFunction::RunImpl() {
   TestConfigState* test_config_state = TestConfigState::GetInstance();
 
   if (!test_config_state->config_state()) {
     error_ = kNoTestConfigDataError;
     return false;
   }
 
-  result_.reset(test_config_state->config_state()->DeepCopy());
+  SetSingleResult(test_config_state->config_state()->DeepCopy());
   return true;
 }