Add wx.DD_DIR_MUST_EXIST style. (Patch #1662736)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@44532 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

wxPython/demo/DirDialog.py

@@ -15,7 +15,10 @@ class TestPanel(wx.Panel):
     def OnButton(self, evt):
         # In this case we include a "New directory" button. 
         dlg = wx.DirDialog(self, "Choose a directory:",
-                          style=wx.DD_DEFAULT_STYLE|wx.DD_NEW_DIR_BUTTON)
+                          style=wx.DD_DEFAULT_STYLE
+                           #| wx.DD_DIR_MUST_EXIST
+                           #| wx.DD_CHANGE_DIR
+                           )
 
         # If the user selects OK, then we process the dialog's data.
         # This is done by getting the path data from the dialog - BEFORE