message: Advertise "mark as unread" count to other extensions
diff: @@ -263,12 +263,19 @@ function updateUnreadIndicator() {
  }
  const statusMark = icon.querySelector('.mail-status');
  const hasRealNotifications = icon.matches('[data-ga-click$=":unread"]');
  + const rghUnreadCount = storage.get().length;
  - const hasUnread = hasRealNotifications || storage.get().length > 0;
  + const hasUnread = hasRealNotifications || rghUnreadCount > 0;
  const label = hasUnread ? 'You have unread notifications' : 'You have no unread notifications';
  icon.setAttribute('aria-label', label);
  statusMark.classList.toggle('unread', hasUnread);
  +
  + if (rghUnreadCount > 0) {
  + icon.dataset.rghUnread = rghUnreadCount; // Store in attribute to let other extensions know
  + } else {
  + delete icon.dataset.rghUnread;
  + }
  }
  function markNotificationRead(e) {
  