Dynamically generate a heading for Extension Docs API pages

chrome/common/extensions/api/tts.json

 // 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.
 
 [
   {
     "namespace": "tts",
+    "description": "Use the <code>chrome.tts</code> module to play synthesized text-to-speech (TTS).",
+    "availability": "Google Chrome 14",
     "types": [
       {
         "id": "TtsEvent",
         "type": "object",
         "description": "An event from the TTS engine to communicate the status of an utterance.",
         "properties": {
           "type": {
             "type": "string",
             "enum": ["start", "end", "word", "sentence", "marker", "interrupted", "cancelled", "error"],
             "description": "The type can be 'start' as soon as speech has started, 'word' when a word boundary is reached, 'sentence' when a sentence boundary is reached, 'marker' when an SSML mark element is reached, 'end' when the end of the utterance is reached, 'interrupted' when the utterance is stopped or interrupted before reaching the end, 'cancelled' when it's removed from the queue before ever being synthesized, or 'error' when any other error occurs."
@@ skipping 212 matching lines @@
             "name": "event",
             "$ref": "TtsEvent",
             "description": "The event from the text-to-speech engine indicating the status of this utterance."
           }
         ],
         "description": "Used to pass events back to the function calling speak()."
       }
     ]
   }
 ]