[css-flexbox] webkit not wrapping with flex-wrap: 0;

After investigating the following Modernizr issue, I discovered a possible
bug in Safari/Webkit:
https://github.com/Modernizr/Modernizr/issues/1414

Webkit does not seem to honor 'flex-wrap' with a -webkit-flex-basis of 0 or
a 'flex: 1;' setting.
Is that a non-complaint to spec bug? Or something left unspecified.

And is this tested in https://bugs.webkit.org/show_bug.cgi?id=136754 ?

It appears fixed/revised in Blink, and semi fixed in Webkit:
https://bugs.webkit.org/show_bug.cgi?id=92324
but not for `flex-basis: 0;` as per jsfiddle snapshots.