ref: 8266b71475d2366a530b34d46a43dce3eceed2ff
parent: 62c20496bf106b1034f4be95bdb7723c3ec78d00
author: Simon Tatham <anakin@pobox.com>
date: Mon Apr 25 18:41:54 EDT 2011
Forgot to set 'has_incentre' on triangular grids, which don't use grid_face_add_new(). Oops. [originally from svn r9161]