Proper API hierarchy between MODULE_LIBS and PRIV_APPS system APIs

Test: build / treehugger
Bug: 146727827
Exempt-From-Owner-Approval: Cherry-picking from goog/master to aosp/master
Merged-in: Ie1ad6711c490c679ebcfacd97154380a8810ba1c
Change-Id: Ie1ad6711c490c679ebcfacd97154380a8810ba1c
3 files changed
tree: 1c6d2f2d8764d77eeedf6fa4168316b79e78786e
  1. Tethering/