Summary:
Enable build file sandboxing in fbandroid.
Importing modules in build files that are not whitelisted will be blocked, this can be overriden by using
with allow_unsafe_import():
import foo
`import os` and `import os.path` will not be blocked and will import a safe version of `os` module instead (functions not accessing the file system like `os.path.join()` will be accessible), full `os` module can be imported using `allow_unsafe_import()`
Reviewed By: plamenko
Differential Revision: D3649817
fbshipit-source-id: 3e6a3ab9c4c6a56a99ca7adf599323143a5844f4