- MenuBarManager::Activate has a check for duplicate activation,
  which makes the second activation attempt fail. Removing this
  check or deactivating after each activation will likely affect
  performance even more, but on the other hand should solve
  lp#1296715, which was the main reason of the over activation
  in the first place. So let's activate only one menu at a time,
  and do full activation only on the initial update.

- Unfortunately the HUD activation callback doesn't work, so
  we still have to keep active status listener for all menu
  items. (Which is BTW against the recommendation in
  XPopupMenuController::updatePopupMenu IDL doc. Fortunately
  the performance problem hardly noticeable on modern hw.)

Change-Id: I96affa72412f3f38160fdca4b6efd20ca68d059f
Reviewed-on: https://gerrit.libreoffice.org/22369Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Maxim Monastirsky <momonasmon@gmail.com>