Summary:
Because we're now separating accessibilityTraits into accessibilityRole and accessibilityState, we're going to only allow one role to be set, and allow on preset combinations of roles that make sense.
This change adds iOS functionality to the role image button because a popular accessibilityTrait combination is image and button.
Reviewed By: ikenwoo
Differential Revision: D8847012
fbshipit-source-id: da386dbf82cb3854d14c228a1116da9f4067fe93