After the document is created, an event is dispatched on the main loop
that calls SfxPickList::Notify(), which modifies document properties.

It tries to prevent setting the document to modified by calling
SfxObjectShell::EnableSetModified(false), but Writer cunningly outwits
it by simply having its own independent(?) modified flag that is set
unconditionally in DocumentStatisticsManager::DocInfoChgd().

Let's assume that if the modified flag shouldn't be modified in
SfxObjectShell, it shouldn't be modified in DocumentStatisticsManager.

Somehow in 4.4 and 4.3 the same thing was going on, but it didn't result
in a visibly enabled Save icon in the UI, but with 5.0 it does - cannot
easily bisect why that changed due to tdf#91383.

Change-Id: Id30fd831eb29910c9fb44ed3031bf8da23586bea