Impacted versions: 8.0

Steps to reproduce:
- Create a database with demo data
- Go to sales, product categories & attributes, attribute values
- Click on 'attribute' column name

Current behavior:
Attribute values are sorted by attribute database ID

Expected behavior:
Attribute values are sorted by attribute name

addons/product/product.py
_name = "product.ul"
    _description = "Logistic Unit"
    _columns = {
        'name' : fields.char('Name', select=True, required=True, translate=True),
        'type' : fields.selection([('unit','Unit'),('pack','Pack'),('box', 'Box'), ('pallet', 'Pallet')], 'Type', required=True),
        'height': fields.float('Height', help='The height of the package'),
        'width': fields.float('Width', help='The width of the package'),
        'length': fields.float('Length', help='The length of the package'),
        'weight': fields.float('Empty Package Weight'),
    }
class product_category(osv.osv):
    @api.multi
    def name_get(self):
        def get_names(cat):
            """ Return the list [cat.name, cat.parent_id.name, ...] """
            res = []
            while cat:
                res.append(cat.name)
                cat = cat.parent_id
            return res
        return [(cat.id, " / ".join(reversed(get_names(cat)))) for cat in self]
    def name_search(self, cr, uid, name, args=None, operator='ilike', context=None, limit=100):