Update sync_events::DeviceLists field types

CHANGELOG.md

@@ -8,6 +8,7 @@ Breaking changes:
 
 * The `event_id` in the response for the message and state sending endpoints is now required
   * r0.6.0 doesn't say they are required, but this has been fixed for the next version of the spec
+* Updated the type of `r0::sync::sync_events::DeviceLists` fields
 
 Improvements:
 

src/r0/sync/sync_events.rs

@@ -330,12 +330,12 @@ pub struct DeviceLists {
     /// List of users who have updated their device identity keys or who now
     /// share an encrypted room with the client since the previous sync
     #[serde(default, skip_serializing_if = "Vec::is_empty")]
-    pub changed: Vec<String>,
+    pub changed: Vec<UserId>,
 
     /// List of users who no longer share encrypted rooms since the previous sync
     /// response.
     #[serde(default, skip_serializing_if = "Vec::is_empty")]
-    pub left: Vec<String>,
+    pub left: Vec<UserId>,
 }
 
 #[cfg(test)]