v18.3.0
Add react-reconciler/constants entry point (#21062)
Support writing to this.refs from userspace
`now` isn't part of the react-reconciler config anymore (#24689)
Refactor Host Config Infra (getting rid of .inline*.js) (#18240)
Bump version from 18.2 to 18.3
Drop the year from Facebook copyright headers and the LICENSE file. (#13593)