One more bug with fix for review and QA.

To reproduce:

1. Add a new saved query that has items that are only highlights (not selected)
2. Make that query the default
3. Clear all filters, add anything else without the highlight that is in the saved query
4. Refresh

Result - the query you refreshed appears, but the highlight from the saved query also appears on top of it.

This is due to us merging the saved query parameters+highlights over the URI params, but the URI params doesn't have the highlights set to 'null' if they're not there, which causes the default to override the state. Fix is in the task.