Fix test after changes in PointOnSurface

git-svn-id: http://svn.osgeo.org/geos/trunk@3833 5242fede-7e19-0410-aef8-94bd7d2200fb
Expose Delaunay triangulation to PHP API (#567)

git-svn-id: http://svn.osgeo.org/geos/trunk@3834 5242fede-7e19-0410-aef8-94bd7d2200fb