Fix up alloc-stress.

- Userspace now uses ranges -1000 to +1000 for oomadj
- Directly call into lmkd instead of writing oom_score-adj; this
  allows alloc-stress to work with userspace lmkd
- If mem cgroups are enabled (future), create a mem cgroup for
  the newly created process.

Change-Id: I4a28eef478cc5a9ad48abdf5bb87c98da3fce3ae
2 files changed