check that document is not None instead of just checking its boolean value

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@28269 20353a03-c40f-0410-a6d1-a30d3c3de9de

bt5/erp5_trade/SkinTemplateItem/portal_skins/erp5_trade/Base_getSpecialisedAggregatedAmountList.xml

@@ -55,7 +55,7 @@
             <key> <string>_body</string> </key>
             <value> <string>specialise = context.getSpecialiseValue(portal_type=(\'Purchase Trade Condition\',\'Sale Trade Condition\'))\n
 \n
-if specialise:\n
+if specialise is not None:\n
   return specialise.getAggregatedAmountList(context)\n
 \n
 return []\n
@@ -100,6 +100,7 @@ return []\n
                             <string>_getattr_</string>
                             <string>context</string>
                             <string>specialise</string>
+                            <string>None</string>
                           </tuple>
                         </value>
                     </item>

bt5/erp5_trade/bt/revision

-708
\ No newline at end of file
+709
\ No newline at end of file