Golden Eye extracts part of it's information about a build from a metadata.json file uploaded along with build artifacts. A "branch" value was only recently added to this file.

Before transitioning release waterfall builds, we need to merge this CL:894844 back to the active release branches.

Before transitioning chromeos.branch builds, we need to invent a better solution. Merging back to all of this is not practical, and many of the older firmware builders upload very old versions of metadata.json, or may not upload it at all.