base: Add three helper functions to Values API.

chrome/browser/extensions/extension_tabs_module.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 "chrome/browser/extensions/extension_tabs_module.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/base64.h"
@@ skipping 572 matching lines @@
   }
   new_window->SelectNumberedTab(0);
 
   if (focused)
     new_window->window()->Show();
   else
     new_window->window()->ShowInactive();
 
   if (new_window->profile()->IsOffTheRecord() && !include_incognito()) {
     // Don't expose incognito windows if the extension isn't allowed.
-    result_.reset(Value::CreateNullValue());
+    result_.reset(base::NullValue());
   } else {
     result_.reset(ExtensionTabUtil::CreateWindowValue(new_window, true));
   }
 
   return true;
 }
 
 bool UpdateWindowFunction::RunImpl() {
   int window_id;
   EXTENSION_FUNCTION_VALIDATE(args_->GetInteger(0, &window_id));
@@ skipping 772 matching lines @@
   // called for every API call the extension made.
   GotLanguage(language);
 }
 
 void DetectTabLanguageFunction::GotLanguage(const std::string& language) {
   result_.reset(Value::CreateStringValue(language.c_str()));
   SendResponse(true);
 
   Release();  // Balanced in Run()
 }