Fix title display for multi-selects
Fix title display for multi-selects

Manually trigger the observers on the selection object for multi-select
dropdowns because setting a property on an observed object doesn't.

SeedScientific/polio,unicef/rhizome,SeedScientific/polio,unicef/polio,unicef/rhizome,unicef/polio,SeedScientific/polio,SeedScientific/polio,unicef/rhizome,unicef/rhizome,unicef/polio,SeedScientific/polio,unicef/polio