[FIX] portal: posting message without token
[FIX] portal: posting message without token

This commit e84779749b14c4f9c9309db1b25c251f3734f5e8 factorize the check of
special access to post a message using a token mecanism, but it breaks the
case without token. Indeed, on some models, it is allow to post a message
on a document when having a certain access. This is handle with the
`_mail_post_access` attribute on model inheriting mail.thread.
Using this mecanism, a user that can read (or write) the document can also
post a message. This is used in the eShop to review product and in blog to
comment blogpost.

This commit restore posting a message without token. the normal access rights
will be applied by message post and raise if the user can not post message,
taking `_mail_post_access` into account.
The balance is now restored in the universe.

Task-1902304
ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo