Frameworks/base: Wall Werror in libs/androidfw

Turn on -Wall -Werror in libs/androidfw. Fix warnings. Refactor
some code.

Change-Id: I66fe54ace433c15dee5de328b149ca142f74b2dd
diff --git a/libs/androidfw/Android.mk b/libs/androidfw/Android.mk
index 376b101..9c0a747 100644
--- a/libs/androidfw/Android.mk
+++ b/libs/androidfw/Android.mk
@@ -52,8 +52,10 @@
 
 LOCAL_CFLAGS += -DSTATIC_ANDROIDFW_FOR_TOOLS
 
+LOCAL_CFLAGS += -Wall -Werror -Wunused -Wunreachable-code
+
 LOCAL_C_INCLUDES := \
-	external/zlib
+    external/zlib
 
 LOCAL_STATIC_LIBRARIES := liblog libziparchive-host libutils
 
@@ -69,11 +71,11 @@
 LOCAL_SRC_FILES:= $(deviceSources)
 
 LOCAL_SHARED_LIBRARIES := \
-	libbinder \
-	liblog \
-	libcutils \
-	libutils \
-	libz
+    libbinder \
+    liblog \
+    libcutils \
+    libutils \
+    libz
 
 LOCAL_STATIC_LIBRARIES := libziparchive
 
@@ -85,6 +87,8 @@
 
 LOCAL_MODULE_TAGS := optional
 
+LOCAL_CFLAGS += -Wall -Werror -Wunused -Wunreachable-code
+
 include $(BUILD_SHARED_LIBRARY)