libbinder_ndk: AIBinder_getCalling(Pid|Uid)

This is for feature-parity w/ the SDK. These methods are of the format
AIBinder_* since they are also static methods on android.os.Binder.

Bug: 111445392
Change-Id: Id33d454936daad492efd3792544f786f9915aa2b
Fixes: 119323183
Test: runtests.sh