"Total Items Count" in IndexStats is incorrent when the number of items change in bucket

"Total Items Count" stat for 2i does not get updated when documents are added/removed from bucket, that impact total number of items indexed.

Repro:

1. In a single node setup, create 10000 docs and a 2i ind1.
The Index Stats "Total Items Count" show correctly 10K

2. Remove a few documents. "Total Items Count" does not get updated.

3. Flush the bucket. "Total Items Count" shows correctly as 0

4. Load 200 documents in the bucket. now the index stats "Total Items Count" for this index shows sometimes 400 and sometimes 0, but never 200.

Screenshots attached.