Interface between audio server and vibrator service

The haptic playback should be controlled by vibrator service. Via the
interface, audio server could notify vibrator service about starting or
stopping haptic playback and get vibrator intensity from vibrator
service. Vibrator service could call mute/unmute to control the haptic
playback.

Test: Manually
Change-Id: Iad24813977e4dea0d67a91f8f8b390a016ce4ca2
diff --git a/media/audioserver/Android.mk b/media/audioserver/Android.mk
index f05c84b..10d8b13 100644
--- a/media/audioserver/Android.mk
+++ b/media/audioserver/Android.mk
@@ -19,7 +19,8 @@
 	libnbaio \
 	libnblog \
 	libsoundtriggerservice \
-	libutils
+	libutils \
+	libvibrator
 
 # TODO oboeservice is the old folder name for aaudioservice. It will be changed.
 LOCAL_C_INCLUDES := \