Impacted versions:
9.0, 10.0

Steps to reproduce:

Create a new database with language English by default and add a new language. Go to settings->translate->languages (in debug mode), inactive English. Go to contacts and "Create". 

Related: https://github.com/odoo/odoo/issues/3854

Current behavior:

Frontend error: Try read en_US language and add to partner, but this not are avalaible.

Expected behavior:
Change default language for all partners.

I need change the default value manually for create new partners:
```
UPDATE public.ir_values
   SET value='S''es_CO''
p1
.'
 WHERE id=1;
```

Video/Screenshot link (optional):


odoo/addons/base/res/res_lang.py
_description = "Languages"
    _order = "active desc,name"
    _disallowed_datetime_patterns = tools.DATETIME_FORMATS_MAP.keys()
    _disallowed_datetime_patterns.remove('%y') 
    name = fields.Char(required=True)
    code = fields.Char(string='Locale Code', required=True, help='This field is used to set/get locales for user')
    iso_code = fields.Char(string='ISO code', help='This ISO code is the name of po files to use for translations')
    translatable = fields.Boolean()
    active = fields.Boolean()
    direction = fields.Selection([('ltr', 'Left-to-Right'), ('rtl', 'Right-to-Left')], required=True, default='ltr')
    date_format = fields.Char(string='Date Format', required=True, default=DEFAULT_DATE_FORMAT)
    time_format = fields.Char(string='Time Format', required=True, default=DEFAULT_TIME_FORMAT)
    grouping = fields.Char(string='Separator Format', required=True, default='[]',
        help="The Separator Format should be like [,n] where 0 < n :starting from Unit digit. "
             "-1 will end the separation. e.g. [3,2,-1] will represent 106500 to be 1,06,500; "
             "[1,2,-1] will represent it to be 106,50,0;[3] will represent it as 106,500. "
             "Provided ',' as the thousand separator in each case.")
    decimal_point = fields.Char(string='Decimal Separator', required=True, default='.')
    thousands_sep = fields.Char(string='Thousands Separator', default=',')
    _sql_constraints = [
        ('name_uniq', 'unique(name)', 'The name of the language must be unique !'),
        ('code_uniq', 'unique(code)', 'The code of the language must be unique !'),
    ]
    @api.constrains('active')
    def _check_active(self):
        
        if self.env.registry.ready and not self.search_count([]):
            raise ValidationError(_('At least one language must be active.'))
    @api.constrains('time_format', 'date_format')
    def _check_format(self):