A couple fixes for the demo, and some code to show a bug

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@11199 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

wxPython/demo/GridCustEditor.py

@@ -46,7 +46,8 @@ class MyCellEditor(wxPyGridCellEditor):
         PaintBackground and do something meaningful there.
         """
         self.log.write("MyCellEditor: SetSize %s\n" % rect)
-        self._tc.SetDimensions(rect.x, rect.y, rect.width+2, rect.height+2)
+        self._tc.SetDimensions(rect.x, rect.y, rect.width+2, rect.height+2,
+                               wxSIZE_ALLOW_MINUS_ONE)
 
 
     def Show(self, show, attr):