Trade Federation is set up in a lightweight "unbundled" branch that uses slightly different build commands from the platform source. In particular, unbundled branches use the tapas command to set up the build environment, rather than the lunch command. So starting from the root directory of the source tree you checked out, try:
$ . build/envsetup.sh
$ tapas tradefed-all
$ m -j8
Note that once the $ . build/envsetup.sh step is done, the other two commands will run equally well from anywhere in the tree.