feat: Don't send Chat-Group-Name* headers for InBroadcast-s

Broadcast subscribers can't change the chat name, so sending the "Chat-Group-Name{,-Timestamp}"
headers looks unnecessary. That could be useful for other subscriber's devices, but having only the
chat name isn't enough anyway, at least knowing the secret is necessary which is sent by the
broadcast owner.

Author: iequidoo

src/chat/chat_tests.rs

@@ -2805,6 +2805,15 @@ async fn test_broadcast_members_cant_see_each_other() -> Result<()> {
             "alice@example.org charlie@example.net"
         );
 
+        // Check additionally that subscribers don't send "Chat-Group-Name*" headers.
+        let parsed = alice.parse_msg(&request_with_auth).await;
+        assert!(parsed.get_header(HeaderDef::ChatGroupName).is_none());
+        assert!(
+            parsed
+                .get_header(HeaderDef::ChatGroupNameTimestamp)
+                .is_none()
+        );
+
         alice.recv_msg_trash(&request_with_auth).await;
     }
 

src/mimefactory.rs

@@ -1394,10 +1394,7 @@ impl MimeFactory {
             }
         }
 
-        if chat.typ == Chattype::Group
-            || chat.typ == Chattype::OutBroadcast
-            || chat.typ == Chattype::InBroadcast
-        {
+        if chat.typ == Chattype::Group || chat.typ == Chattype::OutBroadcast {
             headers.push((
                 "Chat-Group-Name",
                 mail_builder::headers::text::Text::new(chat.name.to_string()).into(),
@@ -1408,7 +1405,11 @@ impl MimeFactory {
                     mail_builder::headers::text::Text::new(ts.to_string()).into(),
                 ));
             }
-
+        }
+        if chat.typ == Chattype::Group
+            || chat.typ == Chattype::OutBroadcast
+            || chat.typ == Chattype::InBroadcast
+        {
             match command {
                 SystemMessage::MemberRemovedFromGroup => {
                     let email_to_remove = msg.param.get(Param::Arg).unwrap_or_default();