Move default_locale out of Extension class

chrome/browser/extensions/api/i18n/i18n_api.h

 // 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_API_I18N_I18N_API_H_
 #define CHROME_BROWSER_EXTENSIONS_API_I18N_I18N_API_H_
 
+#include "chrome/browser/extensions/api/profile_keyed_api_factory.h"
 #include "chrome/browser/extensions/extension_function.h"
 
+class Profile;
+
+namespace extensions {
+
 class I18nGetAcceptLanguagesFunction : public SyncExtensionFunction {
   virtual ~I18nGetAcceptLanguagesFunction() {}
   virtual bool RunImpl() OVERRIDE;
   DECLARE_EXTENSION_FUNCTION("i18n.getAcceptLanguages", I18N_GETACCEPTLANGUAGES)
 };
 
+class I18nAPI : public ProfileKeyedAPI {
+ public:
+  explicit I18nAPI(Profile* profile);
+  virtual ~I18nAPI();
+
+  // ProfileKeyedAPI implementation.
+  static ProfileKeyedAPIFactory<I18nAPI>* GetFactoryInstance();
+
+ private:
+  friend class ProfileKeyedAPIFactory<I18nAPI>;
+
+  // ProfileKeyedAPI implementation.
+  static const char* service_name() {
+    return "I18nAPI";
+  }
+  static const bool kServiceIsNULLWhileTesting = true;
+
+  DISALLOW_COPY_AND_ASSIGN(I18nAPI);
+};
+
+}  // namespace extensions
+
 #endif  // CHROME_BROWSER_EXTENSIONS_API_I18N_I18N_API_H_