If storeToRecoveryFile
has not been called before, this method returns whether the document
has been modified since it has been loaded respectively created.
When saving a session, either in case of a emergency (when OpenOffice.org crashed), or during a
periodic session save as configured by the user, storeToRecoveryFile is called for every
document where wasModifiedSinceLastSave
returns true.
It's allowed to implement this method sloppy, by returning true in cases where it is not sure whether
the document actually has been modified. So, the most simple implementation could simply delegate this call
to ::com::sun::star::util::XModifiable::isModified. (Well, actually that's the
second simple implementation, the most simple one would, still egitimately, always return true.)
However, in such a case, the document might be saved more often than needed. In particular during the
periodic session save, this might become a problem when saving is expensive, for a single document
or the sum of all open documents.