[FIX] bin/workflow: 'stack' variable was not initialized when sql query returned an empty set.
[FIX] bin/workflow: 'stack' variable was not initialized when sql query returned an empty set.

splbio/openobject-server,splbio/openobject-server,MarkusTeufelberger/openobject-server,vnc-biz/openerp-server,xrg/openerp-server,MarkusTeufelberger/openobject-server,xrg/openerp-server,MarkusTeufelberger/openobject-server,gisce/openobject-server,ovnicraft/openerp-server,vnc-biz/openerp-server,gisce/openobject-server,ovnicraft/openerp-server,gisce/openobject-server,splbio/openobject-server