Make the recently accessed folder list globally accessible
This is normally managed by RecentCollectionAction, but is only updated by StandardActionManager when its standard actions are used. If a caller uses its own actions, for example KMail's separate message reader window, then the list is not updated. Add a static function StandardActionManager::addRecentCollection(), which simply calls RecentCollectionAction::addRecentCollection() to update the global recent collection list. Read and update this list in RecentCollectionAction as before. CCBUG:435410