Fix group renaming

[link2xt]

Fixes #6697

Based on #6711

[Hocuri]

I don't really understand how the fix fixes the test, since the test doesn't even have multiple devices that would send sync messages. Maybe the comment could be improved to explain this better, maybe it's fine.

[Hocuri]

I think it would be good to explain this more extensively, because it took me quite a long time to understand it. E.g.:

            // If the change is received from sync message
            // do not update timestamp. It may be long after
            // the group is promoted.
            // (note that `sync == Nosync` would mean
            //that the change comes from a sync message)

[link2xt]

I don't really understand how the fix fixes the test, since the test doesn't even have multiple devices that would send sync messages.

The bug is not about sync messages. Alice is sending old timestamp so the group name is not updated for Bob.

[iequidoo]

The reason of the bug is that MimeFactory::from_msg() loads the chat and then the old (not updated) timestamp is used, so i think the right fix should be just moving this block:

    if msg.param.get_cmd() == SystemMessage::GroupNameChanged {
        msg.chat_id
            .update_timestamp(context, Param::GroupNameTimestamp, msg.timestamp_sort)
            .await?;
    }

above. Using time() may lead to different timestamps in the Date and Chat-Group-Name-Timestamp headers which doesn't look good. And the time() return value isn't aimed for sending out, it's not smeared timestamp.

[iequidoo]

Still, why don't just move the block updating GroupNameTimestamp above? This way we save one db query and also that block goes after

    if recipients.is_empty() {
        // may happen eg. for groups with only SELF and bcc_self disabled                                                                                                                                            
        info!(
            context,
            "Message {} has no recipient, skipping smtp-send.", msg.id
        );
        msg.param.set_int(Param::GuaranteeE2ee, 1);
        msg.update_param(context).await?;
        msg.id.set_delivered(context).await?;
        msg.state = MessageState::OutDelivered;
        return Ok(Vec::new());
    }

which doesn't look good becuse GroupNameTimestamp isn't updated for self-only groups if bcc_self is disabled.

[link2xt]

Still, why don't just move the block updating GroupNameTimestamp above? This way we save one db query and also that block goes after

I have moved it in a separate commit to avoid short-circuit in case of no recipients, but don't see how can it fix the original bug. The problem is with the chat param, not message param, and nothing updates the Chat saved inside the mime parser which is then used when rendering.