Fallback approach for packages with no source

- Some packages have source code that can't be widely released, so we
need to fetch the package in binary form from somewhere. For now,
leverage the packages.tgz of the continuous build, and if the paths for
the code don't exist, extract the desired package from packages.tgz into

Change-Id: I5b63521117c3978a89623466fdcc5c3310f8679d
1 file changed