To view problem, modify an existing use of searchSource with the following

1. searchSource.setField('track_total_hits', 100);.
2. Update searchSource.fetch to include the option legacyHitsTotal: false
3. inspect the results of the search source. Notice that total does not reflect the provided track_total_hits and just returns results like track_total_hits: true was set.

cc @lukasolson