Fix an issue introduced by commit f6920de that results in multiple dropdowns being open at the same time because stopping propagation of the arrow mouse down event in select 2 when opening its dropdown does not allow the blur event to happen for select 1, so the dropdown for select 1 remains open.
Fix an issue introduced by commit f6920de that results in multiple dropdowns being open at the same time because stopping propagation of the arrow mouse down event in select 2 when opening its dropdown does not allow the blur event to happen for select 1, so the dropdown for select 1 remains open.

submittable/react-select,mmpro/react-select,JedWatson/react-select,JedWatson/react-select