Move content settings extension API to content_settings dir.

chrome/browser/content_settings/extension_content_settings_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_EXTENSION_CONTENT_SETTINGS_API_H__
-#define CHROME_BROWSER_EXTENSIONS_EXTENSION_CONTENT_SETTINGS_API_H__
+#ifndef CHROME_BROWSER_CONTENT_SETTINGS_EXTENSION_CONTENT_SETTINGS_API_H__
+#define CHROME_BROWSER_CONTENT_SETTINGS_EXTENSION_CONTENT_SETTINGS_API_H__
 #pragma once
 
 #include "chrome/browser/extensions/extension_function.h"
 
 namespace webkit {
 namespace npapi {
 class PluginGroup;
 }
 }
 
@@ skipping 44 matching lines @@
   FRIEND_TEST_ALL_PREFIXES(ExtensionApiTest,
                            ContentSettingsGetResourceIdentifiers);
 
   void OnGotPluginGroups(const std::vector<webkit::npapi::PluginGroup>& groups);
 
   // Used to override the global plugin list in tests.
   static void SetPluginGroupsForTesting(
       const std::vector<webkit::npapi::PluginGroup>* plugin_groups);
 };
 
-#endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_CONTENT_SETTINGS_API_H__
+#endif  // CHROME_BROWSER_CONTENT_SETTINGS_EXTENSION_CONTENT_SETTINGS_API_H__