Currently, an error occurs when creating a channel that includes guest members.

Steps to Reproduce:
 - Install the `mail` module.
 - Go to `Channels > New`.
 - Fill in the `channel name` and `Under Members`, add a member with a `guest`, and `save`.

`KeyError: 'partner_id'`

This error occurs when a user creates a channel and adds a guest in the Members section. This error occurs after [this commit]( https://github.com/odoo/odoo/commit/ad612321bcafe6dfdaabf3aa37f26af364185a69), where the partner_id and guest_id fields dynamically become readonly [1], so that if only the guest is entered, the partner becomes readonly, and when the record is created, the partner_id key does not exist, and raises the error [2].

This commit ensures that the partner_id is accessed only if it is present in the record.

[1]- https://github.com/odoo/odoo/blob/5bddf9bfb634d09d3264e4fe4734d75f1083775a/addons/mail/views/discuss_channel_views.xml#L87-L88

[2]- https://github.com/odoo/odoo/blob/5bddf9bfb634d09d3264e4fe4734d75f1083775a/addons/mail/models/discuss/discuss_channel.py#L235

sentry-6791956423

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### Issue:

- In the settings enable reception report.
- Create a storable product with a product name of length 60.
- Create and confirm a delivery with 20+ lines of 1 x that product.
- Create and confirm a PO with 20+ lines referring to 1 x that product.
- Validate the receipt > Allocation smart button > Assign all.
- Click on print and open the PDF.
#### > The last row of the first page is cut in half at the end of the page and the beginning of the next one.

### Cause of the issue:

The class `o_report_reception` is used both in the view of the reception report `ReceptionReportMain`:
https://github.com/odoo/odoo/blob/25b8e651c439d688bd05dd0d9619d74fa749597d/addons/stock/static/src/components/reception_report_main/stock_reception_report_main.xml#L16 and its printed version:
https://github.com/odoo/odoo/blob/25b8e651c439d688bd05dd0d9619d74fa749597d/addons/stock/report/report_stock_reception.xml#L43-L44 However, when the report becomes too big (many lines), the class did not allow the user to scroll down the view and a fix has been implemented adding the overflow-y style to the class see https://github.com/odoo/odoo/commit/d8a19285939fb31f6d34290cb8138d402e93024b https://github.com/odoo/odoo/blob/25b8e651c439d688bd05dd0d9619d74fa749597d/addons/stock/static/src/scss/report_stock_reception.scss#L3 The issue being that wkhtmltopdf relies on the size of the table to determine if a row should be displayed on a page or an other one and if you can scroll down he will apparently not do his job correctly.

opw-4824221
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As far as I can tell this can occur if the ws connection gets closed while we're in a `recv`: in that case `recv` will mark the connection as closed (`connected=False` and `sock=None`) and raise `WebSocketConnectionClosedException`, then any attempt to `send` will fail with `WebSocketConnectionClosedException`.

Here this likely is an issue because in `_receive` `WebSocketConnectionClosedException` goes through the generic exception handler, which sees that:

- it's not a `ConnectionResetError`
- the result is not set
- and the ws is not connected

So `_receive` just cancels the result and `return`s, and when whatever's waiting on a future finally times out it tries to cleanly shut down and hits a connection that's already closed.

Handle a connection closed in that context more properly:

- unset `ws` so we don't try to clean it up, as we know it's closed
- set the result as being in error
- cancel every future in order to immediately go to the tour failure step rather than wait for timeouts

Note that this will not really *fix* any error per se, because every time this happens it means the browser abruptly closed the WS connection (possibly straight up died), so this should mostly properly attribute the error so we can investigate it.

https://runbot.odoo.com/odoo/error/229793

Forward-Port-Of: odoo/odoo#224023