Mark CarAppContextManager as @hide. am: 724d95ba5f
am: b2b40bfd26

* commit 'b2b40bfd262de4fb14bded4281c53f7c5d9755c3':
  Mark CarAppContextManager as @hide.

Change-Id: Idff4544ddc6a11bcfc46a2f2dce2bf312315ef71