message: Treat null/undefined notification settings as "not set"
  Otherwise we end up lying and saying notifications are disabled, despite the push rules saying otherwise.
  Part 1 of the fix for:
  *
  *
diff: @@ -40,11 +40,17 @@ export default class DeviceSettingsHandler extends SettingsHandler {
  // Special case notifications
  if (settingName === "notificationsEnabled") {
  - return localStorage.getItem("notifications_enabled") === "true";
  + const value = localStorage.getItem("notifications_enabled");
  + if (typeof(value) === "string") return value === "true";
  + return null; // wrong type or otherwise not set
  } else if (settingName === "notificationBodyEnabled") {
  - return localStorage.getItem("notifications_body_enabled") === "true";
  + const value = localStorage.getItem("notifications_body_enabled");
  + if (typeof(value) === "string") return value === "true";
  + return null; // wrong type or otherwise not set
  } else if (settingName === "audioNotificationsEnabled") {
  - return localStorage.getItem("audio_notifications_enabled") === "true";
  + const value = localStorage.getItem("audio_notifications_enabled");
  + if (typeof(value) === "string") return value === "true";
  + return null; // wrong type or otherwise not set
  }
  return this._getSettings()[settingName];
  