Merge "libbinder: allow stability downgrade" am: 7f284f9697 am: 54d423cde0 am: c8b582fc81

Original change: https://android-review.googlesource.com/c/platform/frameworks/native/+/1649815

Change-Id: Ib59a0c6fdc3f91107857d394c0c5605f8e6e0023