GWT Chrome Extension with manifest_version: 2

问题:

Has any one been able to make a Chrome extension using GWT and manifest_version 2? I have sandboxed all the GWT generated files also (as suggested here) but it still does not work.

manifest.json

{
  "name": "Hello World!",
  "description": "My first packaged app.",
  "manifest_version": 2,
  "version": "0.1",
  "app": {
    "background": {
      "scripts": ["background.js"]
    }
  },
  "permissions": ["experimental", "appWindow"],
  "icons": { "16": "calculator-16.png", "128": "calculator-128.png" }
}

background.js

chrome.experimental.app.onLaunched.addListener(function() {
    chrome.appWindow.create('LocalWebApp.html', {
        'width': 400,
        'height': 500
    });
});

Vishal