Frameworks/native: Wall Werror in batteryservice & powermanager

Turn on -Wall -Werror in services/batteryservice and services/powermanager.
Fix warnings.

Change-Id: I1da667083013379cd8240377c48d63fa5c53033d
diff --git a/services/batteryservice/Android.mk b/services/batteryservice/Android.mk
index 9354b99..e4097d7 100644
--- a/services/batteryservice/Android.mk
+++ b/services/batteryservice/Android.mk
@@ -2,17 +2,19 @@
 include $(CLEAR_VARS)
 
 LOCAL_SRC_FILES:= \
-	BatteryProperties.cpp \
-	BatteryProperty.cpp \
-	IBatteryPropertiesListener.cpp \
-	IBatteryPropertiesRegistrar.cpp
+    BatteryProperties.cpp \
+    BatteryProperty.cpp \
+    IBatteryPropertiesListener.cpp \
+    IBatteryPropertiesRegistrar.cpp
 
 LOCAL_STATIC_LIBRARIES := \
-	libutils \
-	libbinder
+    libutils \
+    libbinder
 
 LOCAL_MODULE:= libbatteryservice
 
 LOCAL_MODULE_TAGS := optional
 
+LOCAL_CFLAGS += -Wall -Werror -Wunused -Wunreachable-code
+
 include $(BUILD_STATIC_LIBRARY)