Summary:
It works great on iOS, and mostly works on Android, and is now OTA'able as part of the screen config! Haven't done template view yet. One remaining issue:
Layout is borked on Android. I'm guessing the issue has to do with the timing of setting the constraints in `updateRootLayoutSpecs` and calling `mBinding.startSurface` which actually builds the shadow tree. If I try to call `updateRootLayoutSpecs` earlier, it just crashes immediately. Here's the layout it spits out, which clearly has -440 for the x of 420006, which is the RCTText component, causing it to get cut off on the left of the screen:
```
updateLayoutMountItem for reactTag: 420006 x: -440, y: -13, width: 931, height: 78
updateLayoutMountItem for reactTag: 420010 x: 26, y: 79, width: 0, height: 1651
updateLayoutMountItem for reactTag: 420012 x: 0, y: 26, width: 0, height: 158
updateLayoutMountItem for reactTag: 420016 x: 0, y: 210, width: 454, height: 454
updateLayoutMountItem for reactTag: 420018 x: 454, y: 210, width: 455, height: 454
updateLayoutMountItem for reactTag: 420022 x: 0, y: 690, width: 454, height: 454
updateLayoutMountItem for reactTag: 420024 x: 454, y: 690, width: 455, height: 454
updateLayoutMountItem for reactTag: 420028 x: 0, y: 1171, width: 454, height: 454
updateLayoutMountItem for reactTag: 420030 x: 454, y: 1171, width: 455, height: 454
updateLayoutMountItem for reactTag: 420032 x: 0, y: 1651, width: 0, height: 0
```
Reviewed By: mdvacca
Differential Revision: D12813192
fbshipit-source-id: 450d646af4883ff25184141721351da67b091b7c
Summary: Adds copyright headers to all files that are missing them.
Reviewed By: hramos
Differential Revision: D12837494
fbshipit-source-id: 6330a18919676dec9ff2c03b7c9329ed9127d930