[Libreoffice] feature/new-autofilter-popup

Hi there,

I've just created another feature branch to replace the current
autofilter popup window with a much nicer one.  If you know the field
button popup window in pivot tables, you'll recognize it since it
re-uses that same popup window class.

During the first phase, I'll just add the same set of menu items that
are in the current autofilter menu i.e. (All, Top 10, Standard Filter,
empty and not empty), to allow fast integration of this feature.  But
since the new popup allows sub menus, I'd like us to explore it to add
easy access to more features in future versions of Calc.

Having said that, even during the initial phase, the new popup will
allow selection of multiple items, as opposed to selection of just one
item as in the current popup.  IIRC, the necessary file format change
has already been proposed to the TC, and (unless it was rejected without
my knowledge) it may even be in the final 1.2 spec.  But I need to
double-check this to be sure.

I'd like to integrate the first phase of this feature in time for 3.5,
but as always, the code freeze date approaching, it's not really a
guarantee & subject to change without notice.

Best,

Kohei

-- 
Kohei Yoshida, LibreOffice hacker, Calc