audio policy: use factory to create audio policy manager

Use the class factory to create the audio policy mamager
instead of AudioPolicyManager class constructor and
use a pointer to an AudioPolicyInterface.

Change-Id: Ibb5a8eee5d597db67cf13f279c909181cfee9949
diff --git a/services/audiopolicy/Android.mk b/services/audiopolicy/Android.mk
index a22ad9d..cddc503 100644
--- a/services/audiopolicy/Android.mk
+++ b/services/audiopolicy/Android.mk
@@ -46,8 +46,8 @@
 
 include $(BUILD_SHARED_LIBRARY)
 
+
 ifneq ($(USE_LEGACY_AUDIO_POLICY), 1)
-ifneq ($(USE_CUSTOM_AUDIO_POLICY), 1)
 
 include $(CLEAR_VARS)
 
@@ -62,6 +62,20 @@
 LOCAL_STATIC_LIBRARIES := \
     libmedia_helper
 
+LOCAL_MODULE:= libaudiopolicymanagerdefault
+
+include $(BUILD_SHARED_LIBRARY)
+
+ifneq ($(USE_CUSTOM_AUDIO_POLICY), 1)
+
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES:= \
+    AudioPolicyFactory.cpp
+
+LOCAL_SHARED_LIBRARIES := \
+    libaudiopolicymanagerdefault
+
 LOCAL_MODULE:= libaudiopolicymanager
 
 include $(BUILD_SHARED_LIBRARY)