Updated gRPC-web code generated files.
Notable changes:
- Using snake_case in proto finally generated proper camelCase here 🎉
- In D10429 I renamed `pre_key` -> `prekey` and `PreKey` -> `Prekey` - lots of changes here related to this
- Left inline comments for other changes
Original TypeScript generated files: https://gist.github.com/barthap/8e92ae580ddc7ba08a45522e46a04eca
Depends on D10430