Use stable version of the INetdEventListener interface

Branches being snapped to release must use stable versions of AIDL
interfaces.

The Merged-In line is from some random change, and is there just to
avoid automerging this change back onto master.

Bug: 167653798
Merged-In: I4fe5b027876bcaa0c6ac13382cae51c4caa60732
Change-Id: I8746f1a32ca1ad32fc3596297b2a0a2a2693d2f3