removing invalid attribute based on c1e1ef80e

[Michael Stahl]

On 07.04.2015 00:46, Markus Mohrhard wrote:
> Hey,
> 
> so going through the calc list of invalid documents I found that you
> documented in c1e1ef80e that we should remove the invalid attribute in a
> few years and make the exported files valid through that.
> 
> I suppose that 3.5 years count as a enough time and we can safely remove
> that attribute now.

guess it's long enough as far as LO is concerned; the old versions that
can't read the correct attribute are probably not used any more.

unfortunately there are a lot of AOO users out there too who can't read
the correct attribute as the bug was never fixed there, but i guess we
can't make everybody happy.