Advice on adding Smart-Art related settings

Hi :)

Lately we have been working on SmartArt support on Writer. As you know,
in 4.1 and prior the SmartArt figures were imported to LO shapes but
they weren't exported back when saving to docx, causing data loss.

Our first approach, which is already pushed to master, was saving the
full SmartArt information in the InteropGrabBag of the shapes and save
it back when exporting to docx. In this situation, users are allowed to
do changes to the shapes but these changes are not saved back.

That takes us to the next step: we want to make imported SmartArt
immutable, so users are aware that they can change the document but not
the shapes. We would like to add a configuration setting to enable or
disable this behaviour, and we have thought of doing it at Options ->
Load/Save -> MS Office. We have some doubts on how to call this
parameter and what should be the default behaviour.

Following the existing conventions in that dialog, we could call the
option "OOXML Smart-Art to LibreOfficeDev".

Right now we think that the proper way would be to mark the load option
always, making the option read only, so the user would not be able to
modify it and will be aware that OOXML SmartArt would always be loaded
and converted.

The second option, saving, would be the selectable one. If we would mark
the option, the Smart-Art will be converted into basic shapes and saved
as such. If it would not be marked, the Smart-Art will be saved as such
in the OOXML documents and, to avoid user modifications, it will be
converted to a bitmap in the UI and saved as such if saved as an
OpenDocument format.

Another topic is whether it would be desirable to let the user select
this option per application. This way, we would have 3 options:
 * "WinWord OOXML Smart-Art to LibreOfficeDev Writer".
 * "Excel OOXML Smart-Art to LibreOfficeDev Calc".
 * "PowerPoint OOXML Smart-Art to LibreOfficeDev Impress".

In the future, if we would have a decent implementation of a similar
functionality of Smart-Art for the OpenDocuments, we would have both
options selectable and the options would say:
 * "WinWord OOXML Smart-Art to LibreOfficeDev Writer or reverse".

Comments? Suggestions?

-- 
Jacobo Aragunde
Software Engineer at Igalia