In this commit, we do two small changes to make it easier to encode
timesheets. The main issue is that we want to solve the following
situation: a user clicks on a cell in a timesheet grid view to open a
list view, then clicks on 'Create' to create a new timesheet. This will
open a form view, but some fields which could be prefilled are not
filled.
- do not reset task_id in some cases. This is important for the onchange
call which comes after a default_get, when there is a default project
value set.
- do not set employee_id if there is default_employee_id in context
This is useful when we open timesheets from the 'All Timesheets'
menu item, then add a new line, select a different employee, and open it
in the grid view (by clicking on the + icon from a cell). This opens a
list view, which is editable, but when we create a new entry, it ignores
the employee value.
Note: a commit in enterprise adds support for properly passing contexts
in grid view, see
https://github.com/odoo/enterprise/commit/f23003917f18b52bb69483cdaac3cb2164230aa6
Task: #35414