[IMP] base: remove merge_states method on res.partner.state model

This function attempted to deduplicate states with same code in order
to force the unique constraint creation. This is the job of a migration
script and should not be execute at each update.
Moreover, the current implementation is flawed and may lead to crash in
some situations.

openerp/addons/base/__openerp__.py

@@ -63,7 +63,6 @@ The kernel of Odoo, needed for all installation.
         'res/ir_property_view.xml',
         'res/res_security.xml',
         'security/ir.model.access.csv',
-        'res/post_base_data.xml', # End because post_process
     ],
     'demo': [
         'base_demo.xml',

openerp/addons/base/res/post_base_data.xml

@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<openerp>
-    <data>
-        <function model="res.country.state" name="merge_states"/>
-    </data>
-</openerp>

openerp/addons/base/res/res_country.py

@@ -98,48 +98,6 @@ class CountryState(models.Model):
 
     name_search = location_name_search
 
-    def merge_states(self, cr, uid, ids=None, context=None):
-        Imd = self.pool['ir.model.data']
-        State = self.pool['res.country.state']
-
-        query = """
-            SELECT st.id, st.oldid, imd.id, imd.name, imd2.id, ids
-            FROM (
-                SELECT st.country_id, st.code, max(st.id) as id, min(st.id) as oldid, string_agg(cast(id as text), ',') as ids
-                FROM res_country_state st
-                GROUP BY st.country_id, st.code
-                HAVING count(*) > 1
-            ) st
-                LEFT JOIN ir_model_data imd on (imd.model = 'res.country.state' and imd.res_id = st.id)
-                LEFT JOIN ir_model_data imd2 on (imd2.model = 'res.country.state' and imd2.res_id = st.oldid)
-            WHERE imd.module = 'base';
-        """
-        cr.execute(query)
-        data = cr.fetchall()
-
-        for st_id, st_oldid, imd_id, imd_name, imd2_id, ids in data:
-            values = dict(module=self._module)
-            if imd2_id:
-                # If duplicated record had already a xml_id we update the old xml_id and
-                # force to delete the new xml_id created to avoid constraint error
-                keepid = imd2_id
-                Imd.unlink(cr, uid, imd_id, context=context)
-                values.update(name=imd_name)
-            else:
-                # Else we point the new xml_id to the oldest duplicated state
-                keepid = imd_id
-                values.update(res_id=st_oldid)
-
-            Imd.write(cr, uid, keepid, values, context=context)
-            State.unlink(cr, uid, st_id, context=context)
-
-            duplicated_ids = set(map(int, ids.split(','))) - set([st_id, st_oldid])
-            if duplicated_ids:
-                _logger.warning(_('State with id [%s] (%s) seems to have duplicated code: %s' % (st_oldid, imd_name, ','.join(duplicated_ids))))
-
-        if data:
-            self._add_sql_constraints(cr)
-
     _sql_constraints = [
         ('name_code_uniq', 'unique(country_id, code)', 'The code of the state must be unique by country !')
     ]