Dynamically generate a heading for Extension Docs API pages

chrome/common/extensions/api/app_window.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.app.window</code> module to create windows. Windows
+// have an optional frame with title bar and size controls. They are not
+// associated with any Chrome browser windows.
+
+[availability=23]
 namespace app.window {
   dictionary Bounds {
     long? left;
     long? top;
     long? width;
     long? height;
   };
 
   // 'shell' is the default window type. 'panel' is managed by the OS
   // (Currently experimental, Ash only).
@@ skipping 188 matching lines @@
     // Fired when the window is maximized.
     [nocompile] static void onMaximized();
 
     // Fired when the window is minimized.
     [nocompile] static void onMinimized();
 
     // Fired when the window is restored from being minimized or maximized.
     [nocompile] static void onRestored();
   };
 };