"Show by Server" displays inconsistent node info at different zoom levels for same stat.

"Show by Server" displays inconsistent node info at different zoom levels for same stat.

Example:
First screenshot is of query specific stat at lower zoom – only query node included as expected. Second screenshot of same query stat at higher zoom is blank and a different node is displayed.

Third screenshot shows cpu utilization at lower zoom - all 3 nodes (data, index, query) included. Fourth screenshot of same stat at higher zoom is blank and has only one node.

This behaviour is side effect of not having samples at higher zoom. Without the sample, menelaus_stats:get_samples_for_system_or_bucket_stat() does not know which Kind (system, bucket, query, index etc) the stat belongs to and the nodes relevant for that Kind i.e. its section_nodes().