Re-enable profile menu for new tab button and restore close button behavior

Summary:
This patch fixes the lack of profile in the new tab button,
and it makes the close button to behave the same way
as the old implementation.

Reviewers: #konsole, sandsmark, hindenburg

Reviewed By: #konsole, hindenburg

Subscribers: konsole-devel

Tags: #konsole

Differential Revision: https://phabricator.kde.org/D14295