Issue 7345 - Use the extension Promise API in release-2018-5
- Don't pass callbacks to any extension API calls that we touched on in release-2018-5.
getPref()in js/desktop-options.js and updated any code that calls it to ensure that the one modified line in which we call it, is compatible with the changes introduced in #323 (closed).
- Cleaned up lengthy callback chain in js/desktop-options.js using
- Updated mock.