Before this commit, the aria-current was the name of the search_X
instead of value 'page'.
Code was strange since `'page' and X` == `X`, while we expect 'page' as
value.
In case of unknown 'search_slide_category' value, use '-' instead to
raise a KeyError Exception.
We still have some links that point to old url with slide category of
type 'presentation' that doesn't exist anymore since the v16.
Remove outdate code following the comment:
> I swear though, don't be afraid, remove it!
From this way, the wrong slide_type of type 'presentation' will be
ignored in all case and link from google will show the slide instead
of an error 500.
closesodoo/odoo#158002
Signed-off-by: Jérémy Kersten <jke@odoo.com>