[FIX] Used Old method for multiple group_by.
[FIX] Used Old method for multiple group_by.

akretion/openerp-web,havt/openerp-web,havt/openerp-web,havt/openerp-web,akretion/openerp-web,havt/openerp-web,havt/openerp-web,akretion/openerp-web