Blender Git Loki

Freestyle: Fix for StrokeVertexIterator.__next__() ignoring the first and only element.

A StrokeVertexIterator ignores the first element when it is the only element.
Such an iterator can be created by the .incremented() method from an iterator
over two stroke vertices.

This problem is a regression from 2.71. The present fix is appropriate to backport
if Blender 2.72a is planned.

Problem report by Kazuhiro Murakawa through personal communications, thanks!