Added support in Helpapp for Manifest Version 2.

BUG=chromium-os:33146
TEST=manual
Review URL: https://chromiumcodereview.appspot.com/10837040

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@149835 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/resources/help_app/manifest.json

@@ -18,5 +18,6 @@
       "all_frames": true
     }
   ],
-  "content_security_policy": "default-src 'self' https://ssl.google-analytics.com http://www.google-analytics.com; frame-src https://www.google.com https://support.google.com; connect-src https://www.google.com https://support.google.com; style-src 'self' 'unsafe-inline'"
+  "manifest_version": 2,
+  "content_security_policy": "default-src 'self'; script-src 'self' https://ssl.google-analytics.com; object-src 'self'; img-src 'self' http://www.google-analytics.com; frame-src https://support.google.com; connect-src https://support.google.com; style-src 'self' 'unsafe-inline'"
 }