Fix for instances of setWorkingDatabase(id) that were used conditionally. Logic for checking null input IDs and returning null was hidden away in setWorkingDatabase(id) code which no longer exists.
Some client code to get entities by ID do pass null input IDs and expect null return (found such instance in org.generationcp.ibpworkbench.ui.programlocations.ProgramLocationsView.initializeValues() where presenter.getFilteredResults(null, this.getSelectedLocationTypeIdFromFilter() is an example of passing null country id which is used to further call locationDataManager.getCountryById(countryId) - when initialising program administration screen) !!!
Keeping such (mad) clients happy with this fix to avoid refactoring them for the moment.

Issue : BMS-167
Reviewer: RebeccaB