TBB needs to include the Go license.
(Per discussion with dcf in legacy/trac#12903 (moved), filing this as a separate ticket from the obfs4 stuff.)
With meek and (soon) obfs4 using Go and certain dependencies, the Go 3 clause BSD license should be distributed as part of the bundles under Browser/TorBrowser/Docs/Licenses/PluggableTransports
.
The license: http://golang.org/LICENSE