Add the currency symbol for the monetary tracking field to better
represent the change of a monetary field.
The currency will be fetch from the currency defined in the
monetary field or on the record's company in case there is not.
For example, if we have a record with a monetary field displaying
"$ 500". If we modify the currency and the value to have "450 €",
the message containing the tracking values will display:
"500 € -> 450 €".
We only use one field to track the currency of a monetary field.
Indeed, in the case where the currency is changed with the value
of a monetary field, only the new currency is tracked. We focus
on the fact that the more important thing is the new value.
Furthermore, when modifying a currency of a monetary field, the
user can already see the new currency before saving the changes.
This allows him to adapt the value of the field if he needs it.
(N.B. we assume that this case will happen very rarely)
Using only one field takes also into account that there are
millions of record for this model and adding a new field would
take a lot of memory.
odoo/odoo#61999odoo/upgrade#2060
task-2387268
Jérémy Hennecart
3a398dc9d9