Merge "Add instructions on how to annotate an AIDL interface" am: b6df9fb2e8 am: b691d9ce36 am: 9e7a44c173 am: 3ced8e8092

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1912992

Change-Id: I1ea1b54a51dea6dd9a65f4a0ee497eec77d36f3b