Merge tag 'android-9.0.0_r37' into staging/lineage-16.0_merge-android-9.0.0_r37

Android 9.0.0 Release 37 (PQ3A.190505.002)

* tag 'android-9.0.0_r37':
  lmkd: bump process priority and set to FOREGROUND group before kill
  Run BoringSSL self test during startup
  Export maximum number of fds/ints in a native_handle.
  Export maximum number of fds/ints in a native_handle.
  usbd: Do not join the thread pool

Change-Id: I73973be25afae5c908ff03a9dbceb302eff323c3