Introduce link classes for media mainline module

Bug: 121239200
Test: make update-api -j / make -j
      atest CtsMediaTestCases:android.media.cts.MediaSessionTest
      atest CtsMediaTestCases:android.media.cts.MediaControllerTest
Change-Id: I93662e83a82f111bfdf25e22525c1466dd66079f
17 files changed