BUG: https://bugs.fuchsia.dev/p/fuchsia/issues/detail?id=87813 As part of the fuchsia platform versioning we are stamping all of our packages with a target api level which can be read by our assembly tools. We would like to be able to update the target api level with a roller so I added a file which can is read by the gn tool. I am open to suggestions about how to change this is we do not want to add file read calls to our gn script.