Camera: allow appdomain FD use for hal_camera

The preview surface will run in app process and hal_camera will
need to wait on FD generated by preview surface.

Test: the denial is gone, able to take photo in
      messenger/hangout/drive application.
Bug: 35589980
Bug: 35485227
Change-Id: I1977174369b104617156065ff25203a17265b707