Summary:
This is required for D5874536, wherein I'll be introducing direction-aware props for borders.
When a view's border changes due to a direction update, only the frames of its children update. Therefore, only the children `UIView`s get a chance to be re-rendered. This is incorrect because the view that's had its borders changed also needs to re-render. So, I keep a track of the layout direction in a property on all shadow views. Then, when I update that prop within `applyLayoutNode`, I push shadow views into the `viewsWithNewFrames` set.
Reviewed By: mmmulani
Differential Revision: D5944488
fbshipit-source-id: 3f23e9973f3555612920703cdb6cec38e6360d2d
9bbc70c442