[css-flexbox] Different behaviour in FF and Chrome regarding flex-basis

Hi,

I'm trying to find out what is the "correct" behaviour according to the
spec and maybe report a bug in one of these browsers.

When a {display:flex} container does not have a height and all its children
have a {flex:1 1 0}, FF collapse the children as if they were not in their
parent Chrome keeps a minimum height.

Test case : http://codepen.io/anon/pen/DreHb

Any clues ?
Thx.

Hubert.