Delete my_dialog_mode_listbox_variation_category_list from erp5_item_trade/Base_viewTradeFieldLibrary because it was overloading
Proxyfield in erp5_trade/Base_viewTradeFieldLibrary with wrong Tales Expression

The purpose of erp5_item_trade/Base_viewTradeFieldLibrary is only to carry new Fields which are not in
erp5_trade/Base_viewTradeFieldLibrary.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@39968 20353a03-c40f-0410-a6d1-a30d3c3de9de