When the user tries to add a barcode without Customer Taxes,
a traceback will appear.

Traceback:
```
AttributeError: 'product.template' object has no attribute 'super'
  File "odoo/http.py", line 2374, in __call__
    response = request._serve_db()
  File "odoo/http.py", line 1904, in _serve_db
    return self._transactioning(
  File "odoo/http.py", line 1967, in _transactioning
    return service_model.retrying(func, env=self.env)
  File "odoo/service/model.py", line 134, in retrying
    result = func()
  File "odoo/http.py", line 1934, in _serve_ir_http
    response = self.dispatcher.dispatch(rule.endpoint, args)
  File "odoo/http.py", line 2178, in dispatch
    result = self.request.registry['ir.http']._dispatch(endpoint)
  File "odoo/addons/base/models/ir_http.py", line 223, in _dispatch
    result = endpoint(**request.params)
  File "odoo/http.py", line 755, in route_wrapper
    result = endpoint(self, *args, **params_ok)
  File "addons/web/controllers/dataset.py", line 35, in call_kw
    return call_kw(request.env[model], method, args, kwargs)
  File "odoo/api.py", line 459, in call_kw
    result = getattr(recs, name)(*args, **kwargs)
  File "addons/web/models/models.py", line 1008, in onchange
    record._apply_onchange_methods(field_name, result)
  File "odoo/models.py", line 7042, in _apply_onchange_methods
    res = method(self)
  File "home/odoo/src/enterprise/saas-17.4/product_barcodelookup/models/product_template.py", line 20, in _onchange_barcode
    product._update_product_by_barcodelookup(product, barcode_lookup_data)
  File "home/odoo/src/enterprise/saas-17.4/product_barcodelookup/models/product_template.py", line 77, in _update_product_by_barcodelookup
    product.list_price = self._get_list_price(price)
  File "addons/account/models/product.py", line 154, in _get_list_price
    return self.super._get_list_price(price)
```

https://github.com/odoo/odoo/blob/42fa237296f9b1fa556ae310b3273f863420e659/addons/account/models/product.py#L146 Here, self.super is used instead of super() .
so, it will lead to the above traceback.

sentry-5766033395

---
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr

Steps to reproduce:
- Install 'Purchase'
- Create a new company with CLP currency.
- Select Chile fiscal localization in Settings.
- Make a new Request for Quotation
- Add any product set price to 23.67
- Add VAT of 19%
- Confirm the order
- Click on the Action button -> Print -> Purchase Order.

Issues:
On the downloaded pdf, the tax base is displayed as "VAT 19% on $24". It shouldn't be the case as we have a single VAT so no need to display this.

The reason for this appearing is because we have a rounding incosistency.

Here we apply `currency.round` on the amount.
https://github.com/odoo/odoo/blob/42fa237296f9b1fa556ae310b3273f863420e659/addons/account/models/account_tax.py#L2116

This is not the case here.
https://github.com/odoo/odoo/blob/42fa237296f9b1fa556ae310b3273f863420e659/addons/account/models/account_tax.py#L2163

Because of this we will have 2 amount in `encountered_base_amounts` whiche means that `'display_tax_base'` will be set to True. https://github.com/odoo/odoo/blob/42fa237296f9b1fa556ae310b3273f863420e659/addons/account/models/account_tax.py#L2188

opw-4039152

Before this commit, when opening a form view of record containing an activity on 2 different tabs, one of tab showed the user avatar while the other doesn't.

Steps to reproduce:
- open Contact form view
- schedule an activity
- open this form view on another tab => the new tab has user avatar on activity while previous tab
   doesn't

This happens because the state of activities is shared between tabs, and the newer tab shares its state to other tabs. However, activity state was not properly passing relational field values notably for the author: instead of passing `type` and `id` identifying values, it only passes `id`. This comes from a typo in code where the `toIdData()` was used on current model (Activity) rather than the target model (Persona), thus only persona id was retrieved.

This commit fixes the issue by properly using `toIdData` on target model of relational field.

Also the date and datetime fields were not properly serialized, which also result in breaking the datetime in other tabs. This commit also fixes this issue.

Task-4143781

Before / After
<img width="300" alt="Screenshot 2024-08-28 at 17 10 25" src="https://github.com/user-attachments/assets/e4422b69-8800-4dc3-ba16-515ea6b7392d"> <img width="369" alt="Screenshot 2024-08-28 at 17 10 30" src="https://github.com/user-attachments/assets/4d5783bd-2935-4630-8ea1-d94264b739bf">