Allow empty timezone selection.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@17625 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5/bootstrap/erp5_core/SkinTemplateItem/portal_skins/erp5_core/Preference_view/my_preferred_time_zone.xml

@@ -179,7 +179,7 @@
       <dictionary>
         <item>
             <key> <string>_text</string> </key>
-            <value> <string>python: [ [x.replace(\'_\', \' \'),  x] for x in here.Base_getCommonTimeZoneList()]</string> </value>
+            <value> <string>python: [[\'\',\'\']] + [[x.replace(\'_\', \' \'),  x] for x in here.Base_getCommonTimeZoneList()]</string> </value>
         </item>
       </dictionary>
     </pickle>

product/ERP5/bootstrap/erp5_core/bt/revision

-568
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+571
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