Remove unneeded intermediary container collection

src/server_server.rs

@@ -1397,10 +1397,10 @@ async fn upgrade_outlier_to_timeline_pdu(
             extremity_sstatehashes.insert(sstatehash, prev_event);
         }
 
-        let mut fork_states = Vec::new();
-
         if okay {
-            for (sstatehash, prev_event) in extremity_sstatehashes {
+            let fork_states: Vec<_> = extremity_sstatehashes
+                .into_iter()
+                .map(|(sstatehash, prev_event)| {
                     let mut leaf_state = db
                         .rooms
                         .state_full_ids(sstatehash)
@@ -1415,21 +1415,16 @@ async fn upgrade_outlier_to_timeline_pdu(
                         // Now it's the state after the pdu
                     }
 
-                fork_states.push(leaf_state);
+                    leaf_state
-            }
-
-            let fork_states = &fork_states
                         .into_iter()
-                .map(|map| {
-                    map.into_iter()
                         .map(|(k, id)| (db.rooms.get_statekey_from_short(k).map(|k| (k, id))))
                         .collect::<Result<StateMap<_>>>()
+                        .map_err(|_| "Failed to get_statekey_from_short.".to_owned())
                 })
-                .collect::<Result<Vec<_>>>()
+                .collect::<StdResult<_, _>>()?;
-                .map_err(|_| "Failed to get_statekey_from_short.".to_owned())?;
 
             let mut auth_chain_sets = Vec::new();
-            for state in fork_states {
+            for state in &fork_states {
                 auth_chain_sets.push(
                     get_auth_chain(
                         &room_id,