* This PR addresses an issue I raised with #1673 where the clipping corner layer doesn't get re-rendered when going from a dark to light user interface style. The fix is to add code in the `-asyncTraitCollectionDidChangeWithPreviousTraitCollection:` method that calls through to `-_updateClipCornerLayerContentsWithRadius:backgroundColor:` if the user interface style changes.
I've also added snapshot tests to verify that using clipping corners with a dynamic background color updates when the user interface style changes.
To preserve dynamic color capabilities for layer-backed
nodes, we need to track backgroundColor as a UIColor. In layer backed nodes we lose the dynamic color logic since we
extract a CGColor from the UIColor applied to ASDisplayNode. With this
change we can respond to changes in UITraitCollection.userInterfaceStyle
for backgroundColor.
vovasty
Harry Shamansky
Rahul Malik
Adlai Holler