Revert previous commit (Fix: 3D axes planes are drawn as triangles)

Author: cgohlke

lib/mpl_toolkits/mplot3d/axis3d.py

@@ -102,7 +102,6 @@ def init3d(self):
 
         # Store dummy data in Polygon object
         self.pane = mpatches.Polygon(np.array([[0,0], [0,1], [1,0], [0,0]]),
-                                    closed=False,
                                     alpha=0.8,
                                     facecolor=(1,1,1,0),
                                     edgecolor=(1,1,1,0))