Impacted versions: 11.0 Enterprise atleast (V9 & 10 too probably)

Steps to reproduce:
1. Create a new database
2. Install the `purchase` module
3. Install the `odoo_studio` module
4. Activate developer mode
5. Go to purchases > purchase orders and create a draft purchase order. Then open up the studio and create a new monetary field. The new field should have the following settings:
- readonly
- required
- widget = monetary
![image](https://user-images.githubusercontent.com/6352350/35973264-0f372f46-0cd5-11e8-8b79-1516c2fa4fef.png)
6. Click on the "More" button and activate tracking for this field too:
![image](https://user-images.githubusercontent.com/6352350/35973298-308bfb18-0cd5-11e8-9475-cafeb447579b.png)
7. Save all these changes and go back to the apps list. Now try to install another app, for example `project`. You'll now get a traceback:
![image](https://user-images.githubusercontent.com/6352350/35973342-52005578-0cd5-11e8-90a5-695706dcf4c9.png)

Current behavior: You cannot install new modules or update existing modules anymore. The `track_visibility` breaks the framework.

Expected behavior: You can install new apps and update existing apps without any issues.


addons/mail/models/ir_model.py
from odoo import _, api, fields, models
from odoo.exceptions import UserError
from odoo.tools import pycompat
class IrModel(models.Model):
    _inherit = 'ir.model'
    _order = 'is_mail_thread DESC, name ASC'
    is_mail_thread = fields.Boolean(
        string="Mail Thread", oldname='mail_thread', default=False,
        help="Whether this model supports messages and notifications.",
    )
    def unlink(self):