Merge "document isBinderAlive" into main am: fd474d7a85

Original change: https://android-review.googlesource.com/c/platform/frameworks/native/+/3165057

Change-Id: I27851e6e392dd13ab810f6e6dc8698107c3eedd0
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>