fix(sync): Deliver device list updates for timeline-only rooms

changelog.d/2175.bugfix

@@ -0,0 +1 @@
+Fixed simplified sliding sync omitting device list updates for rooms with only timeline changes. Contributed by @eleboucher.

src/api/client/sync/v5.rs

@@ -1432,12 +1432,10 @@ where
 			.await
 			.is_ok();
 
-		if let Some(since_shortstatehash) = since_shortstatehash {
+		// Skip the state diff only: `room_keys_changed` below must run for every room.
-			// Skip if there are only timeline changes
+		if let Some(since_shortstatehash) =
-			if since_shortstatehash == current_shortstatehash {
+			since_shortstatehash.filter(|since| *since != current_shortstatehash)
-				continue;
+		{
-			}
-
 			let since_encryption = services
 				.rooms
 				.state_accessor