Revise automatic selection of Results tab

[annehaley]

Right now, the user is automatically taken to the Results tab when the length of the results list has changed. We can't look for any change to the result list because opening a metadata drawer for a region would change every result within the list and therefore trigger the auto selection of the results tab (unexpected behavior).

We need more accurate logic for the results list watcher that will bring the user to the Results tab when that is expected.