Prepare to extract apex/media to packages/modules/Media

- Use Android-Apache-2.0 as default license.

- Adding visibility to non-existing path is there for post-migration
  path [ which currently does not exist ] -- it is not a build error
  to add non-existent paths to visibility.

BUG: 171106157
Test: Local build and TH
Change-Id: I4adea9da4df8f6ae51b9849dfd6a30bf22e28637