Speak Thai chrome extension

manifest.json

{
  "name": "Speak Thai",
  "description": "Reads out selected thai text",
  "version": "0.1",
  "permissions": ["contextMenus"],
  "background": {
    "scripts": ["speak-thai.js"]
  },
  "manifest_version": 2
}

speak-thai.js

var speakThai = function(text){
  var url = 'http://translate.google.co.th/translate_tts?ie=UTF-8&tl=th&q='+text; 
  var audio = new Audio(url);
  audio.play();
};

chrome.contextMenus.create({
  "title" : "Speak Thai",
  "contexts" : ["selection"],
  onclick: function(info, tab) { speakThai(info.selectionText); }
});