Summary:
Changelog: [Internal]
View with `ShadowColor` was getting flattened and therefore views didn't have shadow property set.
This is fixed by promoting ShadowColor so in case it is set, it forms stacking context.
Reviewed By: shergin
Differential Revision: D20792201
fbshipit-source-id: 1033ac00e32047ffbb14e61b7c26348c578d132d