This demanded some code refactoring, and the introduction
of the parent menu property. Updated auto-tests too.

Change-Id: I3d9070b0a1a76d6c174ccf13965d30413f23aadd
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>
Reviewed-by: Caroline Chao <caroline.chao@digia.com>