Add comments to frozen AIDL API files

Generated by re-freezing the API with the new aidl_interface code, and
replacing the previous API with the new files. This only adds comments.

Test: comments only, builds
Bug: 134452637
Merged-In: I983a59d6ecae0c0d49136da723b65a1bb8c9ff53
(cherry picked from commit 44657b8e)

Change-Id: Ie6581f2991152b7e3a7f477097a51b8cbaf0674c