add libvehiclenetwork-audio-helper

- with c wrapper
- update vns to pass event when internal property is set while in
  mocking
- fix bug in VehiclePropValueUtil::copyVehicleProp of deleting non-
  string type.

bug: 	25330290

(cherry picked from commit f1b41f92b11e78373f423343b23229d19cdf0af2)

Change-Id: I54ae1faed1f67528bd2928ce23b53c16d19fcab2
diff --git a/service/src/com/android/car/CarAudioService.java b/service/src/com/android/car/CarAudioService.java
index 77a8ef2..d521d71 100644
--- a/service/src/com/android/car/CarAudioService.java
+++ b/service/src/com/android/car/CarAudioService.java
@@ -325,8 +325,7 @@
 
     private void requestCarProxyFocus(int androidFocus, int flags) {
         mAudioManager.requestAudioFocus(mCarProxyAudioFocusHandler, mAttributeCarExternal,
-                androidFocus,
-                flags);
+                androidFocus, flags, mAudioPolicy);
     }
 
     private void doHandleVolumeChange(VolumeStateChangeEvent event) {