Merge "libbinder_ndk: clarify descriptor encoding" am: fe46e48ea9 am: 8523bb984a am: e9920739a2 am: a8666af893

Original change: https://android-review.googlesource.com/c/platform/frameworks/native/+/1674668

Change-Id: I429a560ca665fbb05a1059fca9a1f196560cfd2f