Enable strict warning checks and fix

Change-Id: Id401a937911eb418e93314812f2f7c2b5ecff8d6
diff --git a/services/audiopolicy/Android.mk b/services/audiopolicy/Android.mk
index 8b45adc..c8e5148 100644
--- a/services/audiopolicy/Android.mk
+++ b/services/audiopolicy/Android.mk
@@ -50,6 +50,7 @@
 LOCAL_MODULE:= libaudiopolicyservice
 
 LOCAL_CFLAGS += -fvisibility=hidden
+LOCAL_CFLAGS += -Wall -Werror
 
 include $(BUILD_SHARED_LIBRARY)
 
@@ -102,6 +103,8 @@
 LOCAL_CFLAGS += -DUSE_XML_AUDIO_POLICY_CONF
 endif #ifeq ($(USE_XML_AUDIO_POLICY_CONF), 1)
 
+LOCAL_CFLAGS += -Wall -Werror
+
 LOCAL_MULTILIB := $(AUDIOSERVER_MULTILIB)
 
 LOCAL_MODULE:= libaudiopolicymanagerdefault
@@ -125,6 +128,8 @@
     $(TOPDIR)frameworks/av/services/audiopolicy/common/include \
     $(TOPDIR)frameworks/av/services/audiopolicy/engine/interface
 
+LOCAL_CFLAGS := -Wall -Werror
+
 LOCAL_MULTILIB := $(AUDIOSERVER_MULTILIB)
 
 LOCAL_MODULE:= libaudiopolicymanager