[css3-background] border-radius: none

Hi,

A designer colleague just wrote `border-radius: none` (to override a 
less specific declaration) and wasted some time trying to "make it work" 
before figuring out that they needed `border-radius: 0`.

Would it make sense to extend the border-radius property (and its 
longhands) to accept the 'none' keyword that would compute to the same 
as '0' ?

Cheers,
-- 
Simon Sapin