Dynamically generate a heading for Extension Docs API pages

chrome/common/extensions/api/sync_file_system.idl

 // 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.
 
+// Use the <code>chrome.syncFileSystem</code> API to save and synchronize data
+// on Google Drive. This API is NOT for accessing arbitrary user docs stored in
+// Google Drive. It provides app-speicif syncable storage for offline and
+// caching usage so that the same data can be available across different
+// clients. Read
+// <a href="http://developer.chrome.com/trunk/apps/app_storage.html">Manage
+// Data</a> for more on using this API.
+
+[availability=dev]
 namespace syncFileSystem {
   enum SyncAction {
     added, updated, deleted
   };
 
   enum ServiceStatus {
     // The sync service is being initialized (e.g. restoring data from the
     // database, checking connectivity and authenticating to the service etc).
     initializing,
 
@@ skipping 157 matching lines @@
     // Fired when an error or other status change has happened in the
     // sync backend (for example, when the sync is temporarily disabled due to
     // network or authentication error).
     static void onServiceStatusChanged(ServiceInfo detail);
 
     // Fired when a file has been updated by the background sync service.
     static void onFileStatusChanged(FileInfo detail);
   };
 
 };