Some extra test to ensure the 100% coverage when real tests are not
needed (I do not want to check everytime that if the coverage is not
100% it is due to something that does not need to be tested such as
"the method returns an empty list if not overriden").


Normally, when defining a multi-objets view, the "list_objects" method
must be overriden to return the ids and title of the objects
displayed. By default, it returns an empty list (that's a fantastic test
I know):

    >>> class FakeRequest(object):
    ...     form = {}

    >>> from collective.mcp.browser.control_panel_page import ControlPanelPage
    >>> my_page = ControlPanelPage(None, FakeRequest())
    >>> my_page.list_objects()
    []
